… | |
… | |
3 | |
3 | |
4 | SYNOPSIS |
4 | SYNOPSIS |
5 | use IO::AIO; |
5 | use IO::AIO; |
6 | |
6 | |
7 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
7 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
8 | my ($fh) = @_; |
8 | my $fh = shift |
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9 | or die "/etc/passwd: $!"; |
9 | ... |
10 | ... |
10 | }; |
11 | }; |
11 | |
12 | |
12 | aio_unlink "/tmp/file", sub { }; |
13 | aio_unlink "/tmp/file", sub { }; |
13 | |
14 | |
… | |
… | |
23 | $req->cancel; # cancel request if still in queue |
24 | $req->cancel; # cancel request if still in queue |
24 | |
25 | |
25 | my $grp = aio_group sub { print "all stats done\n" }; |
26 | my $grp = aio_group sub { print "all stats done\n" }; |
26 | add $grp aio_stat "..." for ...; |
27 | add $grp aio_stat "..." for ...; |
27 | |
28 | |
28 | # AnyEvent integration |
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29 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
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30 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
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31 | |
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32 | # Event integration |
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33 | Event->io (fd => IO::AIO::poll_fileno, |
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34 | poll => 'r', |
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35 | cb => \&IO::AIO::poll_cb); |
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36 | |
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37 | # Glib/Gtk2 integration |
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38 | add_watch Glib::IO IO::AIO::poll_fileno, |
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39 | in => sub { IO::AIO::poll_cb; 1 }; |
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40 | |
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41 | # Tk integration |
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42 | Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "", |
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43 | readable => \&IO::AIO::poll_cb); |
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44 | |
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45 | # Danga::Socket integration |
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46 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
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47 | \&IO::AIO::poll_cb); |
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48 | |
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49 | DESCRIPTION |
29 | DESCRIPTION |
50 | This module implements asynchronous I/O using whatever means your |
30 | This module implements asynchronous I/O using whatever means your |
51 | operating system supports. |
31 | operating system supports. It is implemented as an interface to "libeio" |
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32 | (<http://software.schmorp.de/pkg/libeio.html>). |
52 | |
33 | |
53 | Asynchronous means that operations that can normally block your program |
34 | Asynchronous means that operations that can normally block your program |
54 | (e.g. reading from disk) will be done asynchronously: the operation will |
35 | (e.g. reading from disk) will be done asynchronously: the operation will |
55 | still block, but you can do something else in the meantime. This is |
36 | still block, but you can do something else in the meantime. This is |
56 | extremely useful for programs that need to stay interactive even when |
37 | extremely useful for programs that need to stay interactive even when |
… | |
… | |
60 | faster on a RAID volume or over NFS when you do a number of stat |
41 | faster on a RAID volume or over NFS when you do a number of stat |
61 | operations concurrently. |
42 | operations concurrently. |
62 | |
43 | |
63 | While most of this works on all types of file descriptors (for example |
44 | While most of this works on all types of file descriptors (for example |
64 | sockets), using these functions on file descriptors that support |
45 | sockets), using these functions on file descriptors that support |
65 | nonblocking operation (again, sockets, pipes etc.) is very inefficient |
46 | nonblocking operation (again, sockets, pipes etc.) is very inefficient. |
66 | or might not work (aio_read fails on sockets/pipes/fifos). Use an event |
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67 | loop for that (such as the Event module): IO::AIO will naturally fit |
47 | Use an event loop for that (such as the EV module): IO::AIO will |
68 | into such an event loop itself. |
48 | naturally fit into such an event loop itself. |
69 | |
49 | |
70 | In this version, a number of threads are started that execute your |
50 | In this version, a number of threads are started that execute your |
71 | requests and signal their completion. You don't need thread support in |
51 | requests and signal their completion. You don't need thread support in |
72 | perl, and the threads created by this module will not be visible to |
52 | perl, and the threads created by this module will not be visible to |
73 | perl. In the future, this module might make use of the native aio |
53 | perl. In the future, this module might make use of the native aio |
… | |
… | |
75 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
55 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
76 | files currently, for example), and they would only support aio_read and |
56 | files currently, for example), and they would only support aio_read and |
77 | aio_write, so the remaining functionality would have to be implemented |
57 | aio_write, so the remaining functionality would have to be implemented |
78 | using threads anyway. |
58 | using threads anyway. |
79 | |
59 | |
80 | Although the module will work with in the presence of other (Perl-) |
60 | Although the module will work in the presence of other (Perl-) threads, |
81 | threads, it is currently not reentrant in any way, so use appropriate |
61 | it is currently not reentrant in any way, so use appropriate locking |
82 | locking yourself, always call "poll_cb" from within the same thread, or |
62 | yourself, always call "poll_cb" from within the same thread, or never |
83 | never call "poll_cb" (or other "aio_" functions) recursively. |
63 | call "poll_cb" (or other "aio_" functions) recursively. |
84 | |
64 | |
85 | EXAMPLE |
65 | EXAMPLE |
86 | This is a simple example that uses the Event module and loads |
66 | This is a simple example that uses the EV module and loads /etc/passwd |
87 | /etc/passwd asynchronously: |
67 | asynchronously: |
88 | |
68 | |
89 | use Fcntl; |
69 | use Fcntl; |
90 | use Event; |
70 | use EV; |
91 | use IO::AIO; |
71 | use IO::AIO; |
92 | |
72 | |
93 | # register the IO::AIO callback with Event |
73 | # register the IO::AIO callback with EV |
94 | Event->io (fd => IO::AIO::poll_fileno, |
74 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
95 | poll => 'r', |
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96 | cb => \&IO::AIO::poll_cb); |
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97 | |
75 | |
98 | # queue the request to open /etc/passwd |
76 | # queue the request to open /etc/passwd |
99 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
77 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
100 | my $fh = $_[0] |
78 | my $fh = shift |
101 | or die "error while opening: $!"; |
79 | or die "error while opening: $!"; |
102 | |
80 | |
103 | # stat'ing filehandles is generally non-blocking |
81 | # stat'ing filehandles is generally non-blocking |
104 | my $size = -s $fh; |
82 | my $size = -s $fh; |
105 | |
83 | |
… | |
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113 | |
91 | |
114 | # file contents now in $contents |
92 | # file contents now in $contents |
115 | print $contents; |
93 | print $contents; |
116 | |
94 | |
117 | # exit event loop and program |
95 | # exit event loop and program |
118 | Event::unloop; |
96 | EV::unloop; |
119 | }; |
97 | }; |
120 | }; |
98 | }; |
121 | |
99 | |
122 | # possibly queue up other requests, or open GUI windows, |
100 | # possibly queue up other requests, or open GUI windows, |
123 | # check for sockets etc. etc. |
101 | # check for sockets etc. etc. |
124 | |
102 | |
125 | # process events as long as there are some: |
103 | # process events as long as there are some: |
126 | Event::loop; |
104 | EV::loop; |
127 | |
105 | |
128 | REQUEST ANATOMY AND LIFETIME |
106 | REQUEST ANATOMY AND LIFETIME |
129 | Every "aio_*" function creates a request. which is a C data structure |
107 | Every "aio_*" function creates a request. which is a C data structure |
130 | not directly visible to Perl. |
108 | not directly visible to Perl. |
131 | |
109 | |
… | |
… | |
167 | anymore (except possibly for the Perl object, but its connection to |
145 | anymore (except possibly for the Perl object, but its connection to |
168 | the actual aio request is severed and calling its methods will |
146 | the actual aio request is severed and calling its methods will |
169 | either do nothing or result in a runtime error). |
147 | either do nothing or result in a runtime error). |
170 | |
148 | |
171 | FUNCTIONS |
149 | FUNCTIONS |
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150 | QUICK OVERVIEW |
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151 | This section simply lists the prototypes of the most important functions |
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152 | for quick reference. See the following sections for function-by-function |
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153 | documentation. |
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154 | |
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155 | aio_open $pathname, $flags, $mode, $callback->($fh) |
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156 | aio_close $fh, $callback->($status) |
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157 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
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158 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
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159 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
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160 | aio_readahead $fh,$offset,$length, $callback->($retval) |
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161 | aio_stat $fh_or_path, $callback->($status) |
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162 | aio_lstat $fh, $callback->($status) |
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163 | aio_statvfs $fh_or_path, $callback->($statvfs) |
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164 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
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165 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
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166 | aio_truncate $fh_or_path, $offset, $callback->($status) |
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167 | aio_chmod $fh_or_path, $mode, $callback->($status) |
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168 | aio_unlink $pathname, $callback->($status) |
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169 | aio_mknod $path, $mode, $dev, $callback->($status) |
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170 | aio_link $srcpath, $dstpath, $callback->($status) |
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171 | aio_symlink $srcpath, $dstpath, $callback->($status) |
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172 | aio_readlink $path, $callback->($link) |
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173 | aio_rename $srcpath, $dstpath, $callback->($status) |
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174 | aio_mkdir $pathname, $mode, $callback->($status) |
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175 | aio_rmdir $pathname, $callback->($status) |
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176 | aio_readdir $pathname, $callback->($entries) |
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177 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
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178 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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179 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
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180 | aio_load $path, $data, $callback->($status) |
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181 | aio_copy $srcpath, $dstpath, $callback->($status) |
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182 | aio_move $srcpath, $dstpath, $callback->($status) |
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183 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
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184 | aio_rmtree $path, $callback->($status) |
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185 | aio_sync $callback->($status) |
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186 | aio_fsync $fh, $callback->($status) |
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187 | aio_fdatasync $fh, $callback->($status) |
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188 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
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189 | aio_pathsync $path, $callback->($status) |
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190 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
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191 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
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192 | aio_group $callback->(...) |
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193 | aio_nop $callback->() |
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194 | |
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195 | $prev_pri = aioreq_pri [$pri] |
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196 | aioreq_nice $pri_adjust |
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197 | |
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198 | IO::AIO::poll_wait |
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199 | IO::AIO::poll_cb |
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200 | IO::AIO::poll |
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201 | IO::AIO::flush |
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202 | IO::AIO::max_poll_reqs $nreqs |
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203 | IO::AIO::max_poll_time $seconds |
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204 | IO::AIO::min_parallel $nthreads |
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205 | IO::AIO::max_parallel $nthreads |
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206 | IO::AIO::max_idle $nthreads |
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207 | IO::AIO::max_outstanding $maxreqs |
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208 | IO::AIO::nreqs |
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209 | IO::AIO::nready |
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210 | IO::AIO::npending |
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211 | |
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212 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
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213 | IO::AIO::fadvise $fh, $offset, $len, $advice |
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214 | IO::AIO::mlockall $flags |
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215 | IO::AIO::munlockall |
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216 | |
172 | AIO REQUEST FUNCTIONS |
217 | AIO REQUEST FUNCTIONS |
173 | All the "aio_*" calls are more or less thin wrappers around the syscall |
218 | All the "aio_*" calls are more or less thin wrappers around the syscall |
174 | with the same name (sans "aio_"). The arguments are similar or |
219 | with the same name (sans "aio_"). The arguments are similar or |
175 | identical, and they all accept an additional (and optional) $callback |
220 | identical, and they all accept an additional (and optional) $callback |
176 | argument which must be a code reference. This code reference will get |
221 | argument which must be a code reference. This code reference will get |
177 | called with the syscall return code (e.g. most syscalls return -1 on |
222 | called with the syscall return code (e.g. most syscalls return -1 on |
178 | error, unlike perl, which usually delivers "false") as it's sole |
223 | error, unlike perl, which usually delivers "false") as its sole argument |
179 | argument when the given syscall has been executed asynchronously. |
224 | after the given syscall has been executed asynchronously. |
180 | |
225 | |
181 | All functions expecting a filehandle keep a copy of the filehandle |
226 | All functions expecting a filehandle keep a copy of the filehandle |
182 | internally until the request has finished. |
227 | internally until the request has finished. |
183 | |
228 | |
184 | All functions return request objects of type IO::AIO::REQ that allow |
229 | All functions return request objects of type IO::AIO::REQ that allow |
… | |
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197 | the user environment, d) use Glib::filename_from_unicode on unicode |
242 | the user environment, d) use Glib::filename_from_unicode on unicode |
198 | filenames or e) use something else to ensure your scalar has the correct |
243 | filenames or e) use something else to ensure your scalar has the correct |
199 | contents. |
244 | contents. |
200 | |
245 | |
201 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
246 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
202 | handles correctly wether it is set or not. |
247 | handles correctly whether it is set or not. |
203 | |
248 | |
204 | $prev_pri = aioreq_pri [$pri] |
249 | $prev_pri = aioreq_pri [$pri] |
205 | Returns the priority value that would be used for the next request |
250 | Returns the priority value that would be used for the next request |
206 | and, if $pri is given, sets the priority for the next aio request. |
251 | and, if $pri is given, sets the priority for the next aio request. |
207 | |
252 | |
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241 | They are the same as used by "sysopen". |
286 | They are the same as used by "sysopen". |
242 | |
287 | |
243 | Likewise, $mode specifies the mode of the newly created file, if it |
288 | Likewise, $mode specifies the mode of the newly created file, if it |
244 | didn't exist and "O_CREAT" has been given, just like perl's |
289 | didn't exist and "O_CREAT" has been given, just like perl's |
245 | "sysopen", except that it is mandatory (i.e. use 0 if you don't |
290 | "sysopen", except that it is mandatory (i.e. use 0 if you don't |
246 | create new files, and 0666 or 0777 if you do). |
291 | create new files, and 0666 or 0777 if you do). Note that the $mode |
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292 | will be modified by the umask in effect then the request is being |
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293 | executed, so better never change the umask. |
247 | |
294 | |
248 | Example: |
295 | Example: |
249 | |
296 | |
250 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
297 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
251 | if ($_[0]) { |
298 | if ($_[0]) { |
… | |
… | |
256 | } |
303 | } |
257 | }; |
304 | }; |
258 | |
305 | |
259 | aio_close $fh, $callback->($status) |
306 | aio_close $fh, $callback->($status) |
260 | Asynchronously close a file and call the callback with the result |
307 | Asynchronously close a file and call the callback with the result |
261 | code. *WARNING:* although accepted, you should not pass in a perl |
308 | code. |
262 | filehandle here, as perl will likely close the file descriptor |
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263 | another time when the filehandle is destroyed. Normally, you can |
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264 | safely call perls "close" or just let filehandles go out of scope. |
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265 | |
309 | |
266 | This is supposed to be a bug in the API, so that might change. It's |
310 | Unfortunately, you can't do this to perl. Perl *insists* very |
267 | therefore best to avoid this function. |
311 | strongly on closing the file descriptor associated with the |
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312 | filehandle itself. |
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313 | |
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314 | Therefore, "aio_close" will not close the filehandle - instead it |
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315 | will use dup2 to overwrite the file descriptor with the write-end of |
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316 | a pipe (the pipe fd will be created on demand and will be cached). |
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317 | |
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318 | Or in other words: the file descriptor will be closed, but it will |
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319 | not be free for reuse until the perl filehandle is closed. |
268 | |
320 | |
269 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
321 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
270 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
322 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
271 | Reads or writes "length" bytes from the specified "fh" and "offset" |
323 | Reads or writes $length bytes from or to the specified $fh and |
272 | into the scalar given by "data" and offset "dataoffset" and calls |
324 | $offset into the scalar given by $data and offset $dataoffset and |
273 | the callback without the actual number of bytes read (or -1 on |
325 | calls the callback without the actual number of bytes read (or -1 on |
274 | error, just like the syscall). |
326 | error, just like the syscall). |
275 | |
327 | |
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328 | "aio_read" will, like "sysread", shrink or grow the $data scalar to |
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329 | offset plus the actual number of bytes read. |
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330 | |
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331 | If $offset is undefined, then the current file descriptor offset |
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332 | will be used (and updated), otherwise the file descriptor offset |
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333 | will not be changed by these calls. |
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334 | |
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335 | If $length is undefined in "aio_write", use the remaining length of |
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336 | $data. |
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337 | |
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338 | If $dataoffset is less than zero, it will be counted from the end of |
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339 | $data. |
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340 | |
276 | The $data scalar *MUST NOT* be modified in any way while the request |
341 | The $data scalar *MUST NOT* be modified in any way while the request |
277 | is outstanding. Modifying it can result in segfaults or WW3 (if the |
342 | is outstanding. Modifying it can result in segfaults or World War |
278 | necessary/optional hardware is installed). |
343 | III (if the necessary/optional hardware is installed). |
279 | |
344 | |
280 | Example: Read 15 bytes at offset 7 into scalar $buffer, starting at |
345 | Example: Read 15 bytes at offset 7 into scalar $buffer, starting at |
281 | offset 0 within the scalar: |
346 | offset 0 within the scalar: |
282 | |
347 | |
283 | aio_read $fh, 7, 15, $buffer, 0, sub { |
348 | aio_read $fh, 7, 15, $buffer, 0, sub { |
… | |
… | |
292 | more than one "aio_sendfile" per $out_fh, as they will interfere |
357 | more than one "aio_sendfile" per $out_fh, as they will interfere |
293 | with each other. |
358 | with each other. |
294 | |
359 | |
295 | This call tries to make use of a native "sendfile" syscall to |
360 | This call tries to make use of a native "sendfile" syscall to |
296 | provide zero-copy operation. For this to work, $out_fh should refer |
361 | provide zero-copy operation. For this to work, $out_fh should refer |
297 | to a socket, and $in_fh should refer to mmap'able file. |
362 | to a socket, and $in_fh should refer to an mmap'able file. |
298 | |
363 | |
299 | If the native sendfile call fails or is not implemented, it will be |
364 | If a native sendfile cannot be found or it fails with "ENOSYS", |
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365 | "ENOTSUP", "EOPNOTSUPP", "EAFNOSUPPORT", "EPROTOTYPE" or "ENOTSOCK", |
300 | emulated, so you can call "aio_sendfile" on any type of filehandle |
366 | it will be emulated, so you can call "aio_sendfile" on any type of |
301 | regardless of the limitations of the operating system. |
367 | filehandle regardless of the limitations of the operating system. |
302 | |
368 | |
303 | Please note, however, that "aio_sendfile" can read more bytes from |
369 | Please note, however, that "aio_sendfile" can read more bytes from |
304 | $in_fh than are written, and there is no way to find out how many |
370 | $in_fh than are written, and there is no way to find out how many |
305 | bytes have been read from "aio_sendfile" alone, as "aio_sendfile" |
371 | bytes have been read from "aio_sendfile" alone, as "aio_sendfile" |
306 | only provides the number of bytes written to $out_fh. Only if the |
372 | only provides the number of bytes written to $out_fh. Only if the |
… | |
… | |
341 | aio_stat "/etc/passwd", sub { |
407 | aio_stat "/etc/passwd", sub { |
342 | $_[0] and die "stat failed: $!"; |
408 | $_[0] and die "stat failed: $!"; |
343 | print "size is ", -s _, "\n"; |
409 | print "size is ", -s _, "\n"; |
344 | }; |
410 | }; |
345 | |
411 | |
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412 | aio_statvfs $fh_or_path, $callback->($statvfs) |
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413 | Works like the POSIX "statvfs" or "fstatvfs" syscalls, depending on |
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414 | whether a file handle or path was passed. |
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415 | |
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416 | On success, the callback is passed a hash reference with the |
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417 | following members: "bsize", "frsize", "blocks", "bfree", "bavail", |
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418 | "files", "ffree", "favail", "fsid", "flag" and "namemax". On |
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419 | failure, "undef" is passed. |
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420 | |
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421 | The following POSIX IO::AIO::ST_* constants are defined: "ST_RDONLY" |
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422 | and "ST_NOSUID". |
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423 | |
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424 | The following non-POSIX IO::AIO::ST_* flag masks are defined to |
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425 | their correct value when available, or to 0 on systems that do not |
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426 | support them: "ST_NODEV", "ST_NOEXEC", "ST_SYNCHRONOUS", |
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427 | "ST_MANDLOCK", "ST_WRITE", "ST_APPEND", "ST_IMMUTABLE", |
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428 | "ST_NOATIME", "ST_NODIRATIME" and "ST_RELATIME". |
|
|
429 | |
|
|
430 | Example: stat "/wd" and dump out the data if successful. |
|
|
431 | |
|
|
432 | aio_statvfs "/wd", sub { |
|
|
433 | my $f = $_[0] |
|
|
434 | or die "statvfs: $!"; |
|
|
435 | |
|
|
436 | use Data::Dumper; |
|
|
437 | say Dumper $f; |
|
|
438 | }; |
|
|
439 | |
|
|
440 | # result: |
|
|
441 | { |
|
|
442 | bsize => 1024, |
|
|
443 | bfree => 4333064312, |
|
|
444 | blocks => 10253828096, |
|
|
445 | files => 2050765568, |
|
|
446 | flag => 4096, |
|
|
447 | favail => 2042092649, |
|
|
448 | bavail => 4333064312, |
|
|
449 | ffree => 2042092649, |
|
|
450 | namemax => 255, |
|
|
451 | frsize => 1024, |
|
|
452 | fsid => 1810 |
|
|
453 | } |
|
|
454 | |
|
|
455 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
|
|
456 | Works like perl's "utime" function (including the special case of |
|
|
457 | $atime and $mtime being undef). Fractional times are supported if |
|
|
458 | the underlying syscalls support them. |
|
|
459 | |
|
|
460 | When called with a pathname, uses utimes(2) if available, otherwise |
|
|
461 | utime(2). If called on a file descriptor, uses futimes(2) if |
|
|
462 | available, otherwise returns ENOSYS, so this is not portable. |
|
|
463 | |
|
|
464 | Examples: |
|
|
465 | |
|
|
466 | # set atime and mtime to current time (basically touch(1)): |
|
|
467 | aio_utime "path", undef, undef; |
|
|
468 | # set atime to current time and mtime to beginning of the epoch: |
|
|
469 | aio_utime "path", time, undef; # undef==0 |
|
|
470 | |
|
|
471 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
|
472 | Works like perl's "chown" function, except that "undef" for either |
|
|
473 | $uid or $gid is being interpreted as "do not change" (but -1 can |
|
|
474 | also be used). |
|
|
475 | |
|
|
476 | Examples: |
|
|
477 | |
|
|
478 | # same as "chown root path" in the shell: |
|
|
479 | aio_chown "path", 0, -1; |
|
|
480 | # same as above: |
|
|
481 | aio_chown "path", 0, undef; |
|
|
482 | |
|
|
483 | aio_truncate $fh_or_path, $offset, $callback->($status) |
|
|
484 | Works like truncate(2) or ftruncate(2). |
|
|
485 | |
|
|
486 | aio_chmod $fh_or_path, $mode, $callback->($status) |
|
|
487 | Works like perl's "chmod" function. |
|
|
488 | |
346 | aio_unlink $pathname, $callback->($status) |
489 | aio_unlink $pathname, $callback->($status) |
347 | Asynchronously unlink (delete) a file and call the callback with the |
490 | Asynchronously unlink (delete) a file and call the callback with the |
348 | result code. |
491 | result code. |
349 | |
492 | |
350 | aio_mknod $path, $mode, $dev, $callback->($status) |
493 | aio_mknod $path, $mode, $dev, $callback->($status) |
… | |
… | |
372 | |
515 | |
373 | aio_rename $srcpath, $dstpath, $callback->($status) |
516 | aio_rename $srcpath, $dstpath, $callback->($status) |
374 | Asynchronously rename the object at $srcpath to $dstpath, just as |
517 | Asynchronously rename the object at $srcpath to $dstpath, just as |
375 | rename(2) and call the callback with the result code. |
518 | rename(2) and call the callback with the result code. |
376 | |
519 | |
|
|
520 | aio_mkdir $pathname, $mode, $callback->($status) |
|
|
521 | Asynchronously mkdir (create) a directory and call the callback with |
|
|
522 | the result code. $mode will be modified by the umask at the time the |
|
|
523 | request is executed, so do not change your umask. |
|
|
524 | |
377 | aio_rmdir $pathname, $callback->($status) |
525 | aio_rmdir $pathname, $callback->($status) |
378 | Asynchronously rmdir (delete) a directory and call the callback with |
526 | Asynchronously rmdir (delete) a directory and call the callback with |
379 | the result code. |
527 | the result code. |
380 | |
528 | |
381 | aio_readdir $pathname, $callback->($entries) |
529 | aio_readdir $pathname, $callback->($entries) |
382 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
530 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
383 | entire directory (i.e. opendir + readdir + closedir). The entries |
531 | entire directory (i.e. opendir + readdir + closedir). The entries |
384 | will not be sorted, and will NOT include the "." and ".." entries. |
532 | will not be sorted, and will NOT include the "." and ".." entries. |
385 | |
533 | |
386 | The callback a single argument which is either "undef" or an |
534 | The callback is passed a single argument which is either "undef" or |
387 | array-ref with the filenames. |
535 | an array-ref with the filenames. |
|
|
536 | |
|
|
537 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
|
|
538 | Quite similar to "aio_readdir", but the $flags argument allows to |
|
|
539 | tune behaviour and output format. In case of an error, $entries will |
|
|
540 | be "undef". |
|
|
541 | |
|
|
542 | The flags are a combination of the following constants, ORed |
|
|
543 | together (the flags will also be passed to the callback, possibly |
|
|
544 | modified): |
|
|
545 | |
|
|
546 | IO::AIO::READDIR_DENTS |
|
|
547 | When this flag is off, then the callback gets an arrayref with |
|
|
548 | of names only (as with "aio_readdir"), otherwise it gets an |
|
|
549 | arrayref with "[$name, $type, $inode]" arrayrefs, each |
|
|
550 | describing a single directory entry in more detail. |
|
|
551 | |
|
|
552 | $name is the name of the entry. |
|
|
553 | |
|
|
554 | $type is one of the "IO::AIO::DT_xxx" constants: |
|
|
555 | |
|
|
556 | "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", |
|
|
557 | "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", |
|
|
558 | "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". |
|
|
559 | |
|
|
560 | "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If |
|
|
561 | you need to know, you have to run stat yourself. Also, for speed |
|
|
562 | reasons, the $type scalars are read-only: you can not modify |
|
|
563 | them. |
|
|
564 | |
|
|
565 | $inode is the inode number (which might not be exact on systems |
|
|
566 | with 64 bit inode numbers and 32 bit perls). This field has |
|
|
567 | unspecified content on systems that do not deliver the inode |
|
|
568 | information. |
|
|
569 | |
|
|
570 | IO::AIO::READDIR_DIRS_FIRST |
|
|
571 | When this flag is set, then the names will be returned in an |
|
|
572 | order where likely directories come first. This is useful when |
|
|
573 | you need to quickly find directories, or you want to find all |
|
|
574 | directories while avoiding to stat() each entry. |
|
|
575 | |
|
|
576 | If the system returns type information in readdir, then this is |
|
|
577 | used to find directories directly. Otherwise, likely directories |
|
|
578 | are files beginning with ".", or otherwise files with no dots, |
|
|
579 | of which files with short names are tried first. |
|
|
580 | |
|
|
581 | IO::AIO::READDIR_STAT_ORDER |
|
|
582 | When this flag is set, then the names will be returned in an |
|
|
583 | order suitable for stat()'ing each one. That is, when you plan |
|
|
584 | to stat() all files in the given directory, then the returned |
|
|
585 | order will likely be fastest. |
|
|
586 | |
|
|
587 | If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are |
|
|
588 | specified, then the likely dirs come first, resulting in a less |
|
|
589 | optimal stat order. |
|
|
590 | |
|
|
591 | IO::AIO::READDIR_FOUND_UNKNOWN |
|
|
592 | This flag should not be set when calling "aio_readdirx". |
|
|
593 | Instead, it is being set by "aio_readdirx", when any of the |
|
|
594 | $type's found were "IO::AIO::DT_UNKNOWN". The absense of this |
|
|
595 | flag therefore indicates that all $type's are known, which can |
|
|
596 | be used to speed up some algorithms. |
|
|
597 | |
|
|
598 | aio_load $path, $data, $callback->($status) |
|
|
599 | This is a composite request that tries to fully load the given file |
|
|
600 | into memory. Status is the same as with aio_read. |
388 | |
601 | |
389 | aio_copy $srcpath, $dstpath, $callback->($status) |
602 | aio_copy $srcpath, $dstpath, $callback->($status) |
390 | Try to copy the *file* (directories not supported as either source |
603 | Try to copy the *file* (directories not supported as either source |
391 | or destination) from $srcpath to $dstpath and call the callback with |
604 | or destination) from $srcpath to $dstpath and call the callback with |
392 | the 0 (error) or -1 ok. |
605 | a status of 0 (ok) or -1 (error, see $!). |
393 | |
606 | |
394 | This is a composite request that it creates the destination file |
607 | This is a composite request that creates the destination file with |
395 | with mode 0200 and copies the contents of the source file into it |
608 | mode 0200 and copies the contents of the source file into it using |
396 | using "aio_sendfile", followed by restoring atime, mtime, access |
609 | "aio_sendfile", followed by restoring atime, mtime, access mode and |
397 | mode and uid/gid, in that order. |
610 | uid/gid, in that order. |
398 | |
611 | |
399 | If an error occurs, the partial destination file will be unlinked, |
612 | If an error occurs, the partial destination file will be unlinked, |
400 | if possible, except when setting atime, mtime, access mode and |
613 | if possible, except when setting atime, mtime, access mode and |
401 | uid/gid, where errors are being ignored. |
614 | uid/gid, where errors are being ignored. |
402 | |
615 | |
403 | aio_move $srcpath, $dstpath, $callback->($status) |
616 | aio_move $srcpath, $dstpath, $callback->($status) |
404 | Try to move the *file* (directories not supported as either source |
617 | Try to move the *file* (directories not supported as either source |
405 | or destination) from $srcpath to $dstpath and call the callback with |
618 | or destination) from $srcpath to $dstpath and call the callback with |
406 | the 0 (error) or -1 ok. |
619 | a status of 0 (ok) or -1 (error, see $!). |
407 | |
620 | |
408 | This is a composite request that tries to rename(2) the file first. |
621 | This is a composite request that tries to rename(2) the file first; |
409 | If rename files with "EXDEV", it copies the file with "aio_copy" |
622 | if rename fails with "EXDEV", it copies the file with "aio_copy" |
410 | and, if that is successful, unlinking the $srcpath. |
623 | and, if that is successful, unlinks the $srcpath. |
411 | |
624 | |
412 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
625 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
413 | Scans a directory (similar to "aio_readdir") but additionally tries |
626 | Scans a directory (similar to "aio_readdir") but additionally tries |
414 | to efficiently separate the entries of directory $path into two sets |
627 | to efficiently separate the entries of directory $path into two sets |
415 | of names, directories you can recurse into (directories), and ones |
628 | of names, directories you can recurse into (directories), and ones |
… | |
… | |
435 | Implementation notes. |
648 | Implementation notes. |
436 | |
649 | |
437 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
650 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
438 | can. |
651 | can. |
439 | |
652 | |
|
|
653 | If readdir returns file type information, then this is used directly |
|
|
654 | to find directories. |
|
|
655 | |
440 | After reading the directory, the modification time, size etc. of the |
656 | Otherwise, after reading the directory, the modification time, size |
441 | directory before and after the readdir is checked, and if they match |
657 | etc. of the directory before and after the readdir is checked, and |
442 | (and isn't the current time), the link count will be used to decide |
658 | if they match (and isn't the current time), the link count will be |
443 | how many entries are directories (if >= 2). Otherwise, no knowledge |
659 | used to decide how many entries are directories (if >= 2). |
444 | of the number of subdirectories will be assumed. |
660 | Otherwise, no knowledge of the number of subdirectories will be |
|
|
661 | assumed. |
445 | |
662 | |
446 | Then entries will be sorted into likely directories (everything |
663 | Then entries will be sorted into likely directories a non-initial |
447 | without a non-initial dot currently) and likely non-directories |
664 | dot currently) and likely non-directories (see "aio_readdirx"). Then |
448 | (everything else). Then every entry plus an appended "/." will be |
665 | every entry plus an appended "/." will be "stat"'ed, likely |
449 | "stat"'ed, likely directories first. If that succeeds, it assumes |
666 | directories first, in order of their inode numbers. If that |
450 | that the entry is a directory or a symlink to directory (which will |
667 | succeeds, it assumes that the entry is a directory or a symlink to |
451 | be checked seperately). This is often faster than stat'ing the entry |
668 | directory (which will be checked seperately). This is often faster |
452 | itself because filesystems might detect the type of the entry |
669 | than stat'ing the entry itself because filesystems might detect the |
453 | without reading the inode data (e.g. ext2fs filetype feature). |
670 | type of the entry without reading the inode data (e.g. ext2fs |
|
|
671 | filetype feature), even on systems that cannot return the filetype |
|
|
672 | information on readdir. |
454 | |
673 | |
455 | If the known number of directories (link count - 2) has been |
674 | If the known number of directories (link count - 2) has been |
456 | reached, the rest of the entries is assumed to be non-directories. |
675 | reached, the rest of the entries is assumed to be non-directories. |
457 | |
676 | |
458 | This only works with certainty on POSIX (= UNIX) filesystems, which |
677 | This only works with certainty on POSIX (= UNIX) filesystems, which |
… | |
… | |
460 | |
679 | |
461 | It will also likely work on non-POSIX filesystems with reduced |
680 | It will also likely work on non-POSIX filesystems with reduced |
462 | efficiency as those tend to return 0 or 1 as link counts, which |
681 | efficiency as those tend to return 0 or 1 as link counts, which |
463 | disables the directory counting heuristic. |
682 | disables the directory counting heuristic. |
464 | |
683 | |
|
|
684 | aio_rmtree $path, $callback->($status) |
|
|
685 | Delete a directory tree starting (and including) $path, return the |
|
|
686 | status of the final "rmdir" only. This is a composite request that |
|
|
687 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
|
|
688 | everything else. |
|
|
689 | |
|
|
690 | aio_sync $callback->($status) |
|
|
691 | Asynchronously call sync and call the callback when finished. |
|
|
692 | |
465 | aio_fsync $fh, $callback->($status) |
693 | aio_fsync $fh, $callback->($status) |
466 | Asynchronously call fsync on the given filehandle and call the |
694 | Asynchronously call fsync on the given filehandle and call the |
467 | callback with the fsync result code. |
695 | callback with the fsync result code. |
468 | |
696 | |
469 | aio_fdatasync $fh, $callback->($status) |
697 | aio_fdatasync $fh, $callback->($status) |
470 | Asynchronously call fdatasync on the given filehandle and call the |
698 | Asynchronously call fdatasync on the given filehandle and call the |
471 | callback with the fdatasync result code. |
699 | callback with the fdatasync result code. |
472 | |
700 | |
473 | If this call isn't available because your OS lacks it or it couldn't |
701 | If this call isn't available because your OS lacks it or it couldn't |
474 | be detected, it will be emulated by calling "fsync" instead. |
702 | be detected, it will be emulated by calling "fsync" instead. |
|
|
703 | |
|
|
704 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
|
|
705 | Sync the data portion of the file specified by $offset and $length |
|
|
706 | to disk (but NOT the metadata), by calling the Linux-specific |
|
|
707 | sync_file_range call. If sync_file_range is not available or it |
|
|
708 | returns ENOSYS, then fdatasync or fsync is being substituted. |
|
|
709 | |
|
|
710 | $flags can be a combination of |
|
|
711 | "IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE", |
|
|
712 | "IO::AIO::SYNC_FILE_RANGE_WRITE" and |
|
|
713 | "IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER": refer to the sync_file_range |
|
|
714 | manpage for details. |
|
|
715 | |
|
|
716 | aio_pathsync $path, $callback->($status) |
|
|
717 | This request tries to open, fsync and close the given path. This is |
|
|
718 | a composite request intended to sync directories after directory |
|
|
719 | operations (E.g. rename). This might not work on all operating |
|
|
720 | systems or have any specific effect, but usually it makes sure that |
|
|
721 | directory changes get written to disc. It works for anything that |
|
|
722 | can be opened for read-only, not just directories. |
|
|
723 | |
|
|
724 | Future versions of this function might fall back to other methods |
|
|
725 | when "fsync" on the directory fails (such as calling "sync"). |
|
|
726 | |
|
|
727 | Passes 0 when everything went ok, and -1 on error. |
|
|
728 | |
|
|
729 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, |
|
|
730 | $callback->($status) |
|
|
731 | This is a rather advanced IO::AIO call, which only works on |
|
|
732 | mmap(2)ed scalars (see the "IO::AIO::mmap" function, although it |
|
|
733 | also works on data scalars managed by the Sys::Mmap or Mmap modules, |
|
|
734 | note that the scalar must only be modified in-place while an aio |
|
|
735 | operation is pending on it). |
|
|
736 | |
|
|
737 | It calls the "msync" function of your OS, if available, with the |
|
|
738 | memory area starting at $offset in the string and ending $length |
|
|
739 | bytes later. If $length is negative, counts from the end, and if |
|
|
740 | $length is "undef", then it goes till the end of the string. The |
|
|
741 | flags can be a combination of "IO::AIO::MS_ASYNC", |
|
|
742 | "IO::AIO::MS_INVALIDATE" and "IO::AIO::MS_SYNC". |
|
|
743 | |
|
|
744 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, |
|
|
745 | $callback->($status) |
|
|
746 | This is a rather advanced IO::AIO call, which works best on |
|
|
747 | mmap(2)ed scalars. |
|
|
748 | |
|
|
749 | It touches (reads or writes) all memory pages in the specified range |
|
|
750 | inside the scalar. All caveats and parameters are the same as for |
|
|
751 | "aio_msync", above, except for flags, which must be either 0 (which |
|
|
752 | reads all pages and ensures they are instantiated) or |
|
|
753 | "IO::AIO::MT_MODIFY", which modifies the memory page s(by reading |
|
|
754 | and writing an octet from it, which dirties the page). |
475 | |
755 | |
476 | aio_group $callback->(...) |
756 | aio_group $callback->(...) |
477 | This is a very special aio request: Instead of doing something, it |
757 | This is a very special aio request: Instead of doing something, it |
478 | is a container for other aio requests, which is useful if you want |
758 | is a container for other aio requests, which is useful if you want |
479 | to bundle many requests into a single, composite, request with a |
759 | to bundle many requests into a single, composite, request with a |
… | |
… | |
522 | |
802 | |
523 | cancel $req |
803 | cancel $req |
524 | Cancels the request, if possible. Has the effect of skipping |
804 | Cancels the request, if possible. Has the effect of skipping |
525 | execution when entering the execute state and skipping calling the |
805 | execution when entering the execute state and skipping calling the |
526 | callback when entering the the result state, but will leave the |
806 | callback when entering the the result state, but will leave the |
527 | request otherwise untouched. That means that requests that currently |
807 | request otherwise untouched (with the exception of readdir). That |
528 | execute will not be stopped and resources held by the request will |
808 | means that requests that currently execute will not be stopped and |
529 | not be freed prematurely. |
809 | resources held by the request will not be freed prematurely. |
530 | |
810 | |
531 | cb $req $callback->(...) |
811 | cb $req $callback->(...) |
532 | Replace (or simply set) the callback registered to the request. |
812 | Replace (or simply set) the callback registered to the request. |
533 | |
813 | |
534 | IO::AIO::GRP CLASS |
814 | IO::AIO::GRP CLASS |
… | |
… | |
561 | }; |
841 | }; |
562 | |
842 | |
563 | This makes it very easy to create composite requests (see the source of |
843 | This makes it very easy to create composite requests (see the source of |
564 | "aio_move" for an application) that work and feel like simple requests. |
844 | "aio_move" for an application) that work and feel like simple requests. |
565 | |
845 | |
566 | * The IO::AIO::GRP objects will be cleaned up during calls to |
846 | * The IO::AIO::GRP objects will be cleaned up during calls to |
567 | "IO::AIO::poll_cb", just like any other request. |
847 | "IO::AIO::poll_cb", just like any other request. |
|
|
848 | |
568 | * They can be canceled like any other request. Canceling will cancel not |
849 | * They can be canceled like any other request. Canceling will cancel |
569 | only the request itself, but also all requests it contains. |
850 | not only the request itself, but also all requests it contains. |
|
|
851 | |
570 | * They can also can also be added to other IO::AIO::GRP objects. |
852 | * They can also can also be added to other IO::AIO::GRP objects. |
|
|
853 | |
571 | * You must not add requests to a group from within the group callback |
854 | * You must not add requests to a group from within the group callback |
572 | (or any later time). |
855 | (or any later time). |
573 | |
856 | |
574 | Their lifetime, simplified, looks like this: when they are empty, they |
857 | Their lifetime, simplified, looks like this: when they are empty, they |
575 | will finish very quickly. If they contain only requests that are in the |
858 | will finish very quickly. If they contain only requests that are in the |
576 | "done" state, they will also finish. Otherwise they will continue to |
859 | "done" state, they will also finish. Otherwise they will continue to |
577 | exist. |
860 | exist. |
578 | |
861 | |
579 | That means after creating a group you have some time to add requests. |
862 | That means after creating a group you have some time to add requests |
580 | And in the callbacks of those requests, you can add further requests to |
863 | (precisely before the callback has been invoked, which is only done |
581 | the group. And only when all those requests have finished will the the |
864 | within the "poll_cb"). And in the callbacks of those requests, you can |
582 | group itself finish. |
865 | add further requests to the group. And only when all those requests have |
|
|
866 | finished will the the group itself finish. |
583 | |
867 | |
584 | add $grp ... |
868 | add $grp ... |
585 | $grp->add (...) |
869 | $grp->add (...) |
586 | Add one or more requests to the group. Any type of IO::AIO::REQ can |
870 | Add one or more requests to the group. Any type of IO::AIO::REQ can |
587 | be added, including other groups, as long as you do not create |
871 | be added, including other groups, as long as you do not create |
… | |
… | |
592 | $grp->cancel_subs |
876 | $grp->cancel_subs |
593 | Cancel all subrequests and clears any feeder, but not the group |
877 | Cancel all subrequests and clears any feeder, but not the group |
594 | request itself. Useful when you queued a lot of events but got a |
878 | request itself. Useful when you queued a lot of events but got a |
595 | result early. |
879 | result early. |
596 | |
880 | |
|
|
881 | The group request will finish normally (you cannot add requests to |
|
|
882 | the group). |
|
|
883 | |
597 | $grp->result (...) |
884 | $grp->result (...) |
598 | Set the result value(s) that will be passed to the group callback |
885 | Set the result value(s) that will be passed to the group callback |
599 | when all subrequests have finished and set thre groups errno to the |
886 | when all subrequests have finished and set the groups errno to the |
600 | current value of errno (just like calling "errno" without an error |
887 | current value of errno (just like calling "errno" without an error |
601 | number). By default, no argument will be passed and errno is zero. |
888 | number). By default, no argument will be passed and errno is zero. |
602 | |
889 | |
603 | $grp->errno ([$errno]) |
890 | $grp->errno ([$errno]) |
604 | Sets the group errno value to $errno, or the current value of errno |
891 | Sets the group errno value to $errno, or the current value of errno |
… | |
… | |
630 | does not impose any limits). |
917 | does not impose any limits). |
631 | |
918 | |
632 | If the feed does not queue more requests when called, it will be |
919 | If the feed does not queue more requests when called, it will be |
633 | automatically removed from the group. |
920 | automatically removed from the group. |
634 | |
921 | |
635 | If the feed limit is 0, it will be set to 2 automatically. |
922 | If the feed limit is 0 when this method is called, it will be set to |
|
|
923 | 2 automatically. |
636 | |
924 | |
637 | Example: |
925 | Example: |
638 | |
926 | |
639 | # stat all files in @files, but only ever use four aio requests concurrently: |
927 | # stat all files in @files, but only ever use four aio requests concurrently: |
640 | |
928 | |
… | |
… | |
651 | Sets the feeder limit for the group: The feeder will be called |
939 | Sets the feeder limit for the group: The feeder will be called |
652 | whenever the group contains less than this many requests. |
940 | whenever the group contains less than this many requests. |
653 | |
941 | |
654 | Setting the limit to 0 will pause the feeding process. |
942 | Setting the limit to 0 will pause the feeding process. |
655 | |
943 | |
|
|
944 | The default value for the limit is 0, but note that setting a feeder |
|
|
945 | automatically bumps it up to 2. |
|
|
946 | |
656 | SUPPORT FUNCTIONS |
947 | SUPPORT FUNCTIONS |
657 | EVENT PROCESSING AND EVENT LOOP INTEGRATION |
948 | EVENT PROCESSING AND EVENT LOOP INTEGRATION |
658 | $fileno = IO::AIO::poll_fileno |
949 | $fileno = IO::AIO::poll_fileno |
659 | Return the *request result pipe file descriptor*. This filehandle |
950 | Return the *request result pipe file descriptor*. This filehandle |
660 | must be polled for reading by some mechanism outside this module |
951 | must be polled for reading by some mechanism outside this module |
661 | (e.g. Event or select, see below or the SYNOPSIS). If the pipe |
952 | (e.g. EV, Glib, select and so on, see below or the SYNOPSIS). If the |
662 | becomes readable you have to call "poll_cb" to check the results. |
953 | pipe becomes readable you have to call "poll_cb" to check the |
|
|
954 | results. |
663 | |
955 | |
664 | See "poll_cb" for an example. |
956 | See "poll_cb" for an example. |
665 | |
957 | |
666 | IO::AIO::poll_cb |
958 | IO::AIO::poll_cb |
667 | Process some outstanding events on the result pipe. You have to call |
959 | Process some outstanding events on the result pipe. You have to call |
668 | this regularly. Returns the number of events processed. Returns |
960 | this regularly. Returns 0 if all events could be processed, or -1 if |
669 | immediately when no events are outstanding. The amount of events |
961 | it returned earlier for whatever reason. Returns immediately when no |
|
|
962 | events are outstanding. The amount of events processed depends on |
670 | processed depends on the settings of "IO::AIO::max_poll_req" and |
963 | the settings of "IO::AIO::max_poll_req" and |
671 | "IO::AIO::max_poll_time". |
964 | "IO::AIO::max_poll_time". |
672 | |
965 | |
673 | If not all requests were processed for whatever reason, the |
966 | If not all requests were processed for whatever reason, the |
674 | filehandle will still be ready when "poll_cb" returns. |
967 | filehandle will still be ready when "poll_cb" returns, so normally |
|
|
968 | you don't have to do anything special to have it called later. |
675 | |
969 | |
676 | Example: Install an Event watcher that automatically calls |
970 | Example: Install an Event watcher that automatically calls |
677 | IO::AIO::poll_cb with high priority: |
971 | IO::AIO::poll_cb with high priority (more examples can be found in |
|
|
972 | the SYNOPSIS section, at the top of this document): |
678 | |
973 | |
679 | Event->io (fd => IO::AIO::poll_fileno, |
974 | Event->io (fd => IO::AIO::poll_fileno, |
680 | poll => 'r', async => 1, |
975 | poll => 'r', async => 1, |
681 | cb => \&IO::AIO::poll_cb); |
976 | cb => \&IO::AIO::poll_cb); |
|
|
977 | |
|
|
978 | IO::AIO::poll_wait |
|
|
979 | If there are any outstanding requests and none of them in the result |
|
|
980 | phase, wait till the result filehandle becomes ready for reading |
|
|
981 | (simply does a "select" on the filehandle. This is useful if you |
|
|
982 | want to synchronously wait for some requests to finish). |
|
|
983 | |
|
|
984 | See "nreqs" for an example. |
|
|
985 | |
|
|
986 | IO::AIO::poll |
|
|
987 | Waits until some requests have been handled. |
|
|
988 | |
|
|
989 | Returns the number of requests processed, but is otherwise strictly |
|
|
990 | equivalent to: |
|
|
991 | |
|
|
992 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
993 | |
|
|
994 | IO::AIO::flush |
|
|
995 | Wait till all outstanding AIO requests have been handled. |
|
|
996 | |
|
|
997 | Strictly equivalent to: |
|
|
998 | |
|
|
999 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1000 | while IO::AIO::nreqs; |
682 | |
1001 | |
683 | IO::AIO::max_poll_reqs $nreqs |
1002 | IO::AIO::max_poll_reqs $nreqs |
684 | IO::AIO::max_poll_time $seconds |
1003 | IO::AIO::max_poll_time $seconds |
685 | These set the maximum number of requests (default 0, meaning |
1004 | These set the maximum number of requests (default 0, meaning |
686 | infinity) that are being processed by "IO::AIO::poll_cb" in one |
1005 | infinity) that are being processed by "IO::AIO::poll_cb" in one |
… | |
… | |
710 | # use a low priority so other tasks have priority |
1029 | # use a low priority so other tasks have priority |
711 | Event->io (fd => IO::AIO::poll_fileno, |
1030 | Event->io (fd => IO::AIO::poll_fileno, |
712 | poll => 'r', nice => 1, |
1031 | poll => 'r', nice => 1, |
713 | cb => &IO::AIO::poll_cb); |
1032 | cb => &IO::AIO::poll_cb); |
714 | |
1033 | |
715 | IO::AIO::poll_wait |
|
|
716 | Wait till the result filehandle becomes ready for reading (simply |
|
|
717 | does a "select" on the filehandle. This is useful if you want to |
|
|
718 | synchronously wait for some requests to finish). |
|
|
719 | |
|
|
720 | See "nreqs" for an example. |
|
|
721 | |
|
|
722 | IO::AIO::poll |
|
|
723 | Waits until some requests have been handled. |
|
|
724 | |
|
|
725 | Strictly equivalent to: |
|
|
726 | |
|
|
727 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
728 | if IO::AIO::nreqs; |
|
|
729 | |
|
|
730 | IO::AIO::flush |
|
|
731 | Wait till all outstanding AIO requests have been handled. |
|
|
732 | |
|
|
733 | Strictly equivalent to: |
|
|
734 | |
|
|
735 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
736 | while IO::AIO::nreqs; |
|
|
737 | |
|
|
738 | CONTROLLING THE NUMBER OF THREADS |
1034 | CONTROLLING THE NUMBER OF THREADS |
739 | IO::AIO::min_parallel $nthreads |
1035 | IO::AIO::min_parallel $nthreads |
740 | Set the minimum number of AIO threads to $nthreads. The current |
1036 | Set the minimum number of AIO threads to $nthreads. The current |
741 | default is 8, which means eight asynchronous operations can execute |
1037 | default is 8, which means eight asynchronous operations can execute |
742 | concurrently at any one time (the number of outstanding requests, |
1038 | concurrently at any one time (the number of outstanding requests, |
… | |
… | |
784 | |
1080 | |
785 | The default is probably ok in most situations, especially if thread |
1081 | The default is probably ok in most situations, especially if thread |
786 | creation is fast. If thread creation is very slow on your system you |
1082 | creation is fast. If thread creation is very slow on your system you |
787 | might want to use larger values. |
1083 | might want to use larger values. |
788 | |
1084 | |
789 | $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
1085 | IO::AIO::max_outstanding $maxreqs |
790 | This is a very bad function to use in interactive programs because |
1086 | This is a very bad function to use in interactive programs because |
791 | it blocks, and a bad way to reduce concurrency because it is |
1087 | it blocks, and a bad way to reduce concurrency because it is |
792 | inexact: Better use an "aio_group" together with a feed callback. |
1088 | inexact: Better use an "aio_group" together with a feed callback. |
793 | |
1089 | |
794 | Sets the maximum number of outstanding requests to $nreqs. If you to |
1090 | Sets the maximum number of outstanding requests to $nreqs. If you do |
795 | queue up more than this number of requests, the next call to the |
1091 | queue up more than this number of requests, the next call to the |
796 | "poll_cb" (and "poll_some" and other functions calling "poll_cb") |
1092 | "poll_cb" (and "poll_some" and other functions calling "poll_cb") |
797 | function will block until the limit is no longer exceeded. |
1093 | function will block until the limit is no longer exceeded. |
798 | |
1094 | |
799 | The default value is very large, so there is no practical limit on |
1095 | The default value is very large, so there is no practical limit on |
800 | the number of outstanding requests. |
1096 | the number of outstanding requests. |
801 | |
1097 | |
802 | You can still queue as many requests as you want. Therefore, |
1098 | You can still queue as many requests as you want. Therefore, |
803 | "max_oustsanding" is mainly useful in simple scripts (with low |
1099 | "max_outstanding" is mainly useful in simple scripts (with low |
804 | values) or as a stop gap to shield against fatal memory overflow |
1100 | values) or as a stop gap to shield against fatal memory overflow |
805 | (with large values). |
1101 | (with large values). |
806 | |
1102 | |
807 | STATISTICAL INFORMATION |
1103 | STATISTICAL INFORMATION |
808 | IO::AIO::nreqs |
1104 | IO::AIO::nreqs |
… | |
… | |
820 | executed). |
1116 | executed). |
821 | |
1117 | |
822 | IO::AIO::npending |
1118 | IO::AIO::npending |
823 | Returns the number of requests currently in the pending state |
1119 | Returns the number of requests currently in the pending state |
824 | (executed, but not yet processed by poll_cb). |
1120 | (executed, but not yet processed by poll_cb). |
|
|
1121 | |
|
|
1122 | MISCELLANEOUS FUNCTIONS |
|
|
1123 | IO::AIO implements some functions that might be useful, but are not |
|
|
1124 | asynchronous. |
|
|
1125 | |
|
|
1126 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
|
|
1127 | Calls the "eio_sendfile_sync" function, which is like |
|
|
1128 | "aio_sendfile", but is blocking (this makes most sense if you know |
|
|
1129 | the input data is likely cached already and the output filehandle is |
|
|
1130 | set to non-blocking operations). |
|
|
1131 | |
|
|
1132 | Returns the number of bytes copied, or -1 on error. |
|
|
1133 | |
|
|
1134 | IO::AIO::fadvise $fh, $offset, $len, $advice |
|
|
1135 | Simply calls the "posix_fadvise" function (see it's manpage for |
|
|
1136 | details). The following advice constants are avaiable: |
|
|
1137 | "IO::AIO::FADV_NORMAL", "IO::AIO::FADV_SEQUENTIAL", |
|
|
1138 | "IO::AIO::FADV_RANDOM", "IO::AIO::FADV_NOREUSE", |
|
|
1139 | "IO::AIO::FADV_WILLNEED", "IO::AIO::FADV_DONTNEED". |
|
|
1140 | |
|
|
1141 | On systems that do not implement "posix_fadvise", this function |
|
|
1142 | returns ENOSYS, otherwise the return value of "posix_fadvise". |
|
|
1143 | |
|
|
1144 | IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
|
|
1145 | Memory-maps a file (or anonymous memory range) and attaches it to |
|
|
1146 | the given $scalar, which will act like a string scalar. |
|
|
1147 | |
|
|
1148 | The only operations allowed on the scalar are "substr"/"vec" that |
|
|
1149 | don't change the string length, and most read-only operations such |
|
|
1150 | as copying it or searching it with regexes and so on. |
|
|
1151 | |
|
|
1152 | Anything else is unsafe and will, at best, result in memory leaks. |
|
|
1153 | |
|
|
1154 | The memory map associated with the $scalar is automatically removed |
|
|
1155 | when the $scalar is destroyed, or when the "IO::AIO::mmap" or |
|
|
1156 | "IO::AIO::munmap" functions are called. |
|
|
1157 | |
|
|
1158 | This calls the "mmap"(2) function internally. See your system's |
|
|
1159 | manual page for details on the $length, $prot and $flags parameters. |
|
|
1160 | |
|
|
1161 | The $length must be larger than zero and smaller than the actual |
|
|
1162 | filesize. |
|
|
1163 | |
|
|
1164 | $prot is a combination of "IO::AIO::PROT_NONE", |
|
|
1165 | "IO::AIO::PROT_EXEC", "IO::AIO::PROT_READ" and/or |
|
|
1166 | "IO::AIO::PROT_WRITE", |
|
|
1167 | |
|
|
1168 | $flags can be a combination of "IO::AIO::MAP_SHARED" or |
|
|
1169 | "IO::AIO::MAP_PRIVATE", or a number of system-specific flags (when |
|
|
1170 | not available, the are defined as 0): "IO::AIO::MAP_ANONYMOUS" |
|
|
1171 | (which is set to "MAP_ANON" if your system only provides this |
|
|
1172 | constant), "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_LOCKED", |
|
|
1173 | "IO::AIO::MAP_NORESERVE", "IO::AIO::MAP_POPULATE" or |
|
|
1174 | "IO::AIO::MAP_NONBLOCK" |
|
|
1175 | |
|
|
1176 | If $fh is "undef", then a file descriptor of -1 is passed. |
|
|
1177 | |
|
|
1178 | $offset is the offset from the start of the file - it generally must |
|
|
1179 | be a multiple of "IO::AIO::PAGESIZE" and defaults to 0. |
|
|
1180 | |
|
|
1181 | Example: |
|
|
1182 | |
|
|
1183 | use Digest::MD5; |
|
|
1184 | use IO::AIO; |
|
|
1185 | |
|
|
1186 | open my $fh, "<verybigfile" |
|
|
1187 | or die "$!"; |
|
|
1188 | |
|
|
1189 | IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh |
|
|
1190 | or die "verybigfile: $!"; |
|
|
1191 | |
|
|
1192 | my $fast_md5 = md5 $data; |
|
|
1193 | |
|
|
1194 | IO::AIO::munmap $scalar |
|
|
1195 | Removes a previous mmap and undefines the $scalar. |
|
|
1196 | |
|
|
1197 | IO::AIO::mlockall $flags |
|
|
1198 | Calls the "mlockall" function with the given $flags (a combination |
|
|
1199 | of "IO::AIO::MCL_CURRENT" and "IO::AIO::MCL__FUTURE"). |
|
|
1200 | |
|
|
1201 | On systems that do not implement "mlockall", this function returns |
|
|
1202 | ENOSYS, otherwise the return value of "mlockall". |
|
|
1203 | |
|
|
1204 | IO::AIO::munlockall |
|
|
1205 | Calls the "munlockall" function. |
|
|
1206 | |
|
|
1207 | On systems that do not implement "munlockall", this function returns |
|
|
1208 | ENOSYS, otherwise the return value of "munlockall". |
|
|
1209 | |
|
|
1210 | EVENT LOOP INTEGRATION |
|
|
1211 | It is recommended to use AnyEvent::AIO to integrate IO::AIO |
|
|
1212 | automatically into many event loops: |
|
|
1213 | |
|
|
1214 | # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...) |
|
|
1215 | use AnyEvent::AIO; |
|
|
1216 | |
|
|
1217 | You can also integrate IO::AIO manually into many event loops, here are |
|
|
1218 | some examples of how to do this: |
|
|
1219 | |
|
|
1220 | # EV integration |
|
|
1221 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
|
|
1222 | |
|
|
1223 | # Event integration |
|
|
1224 | Event->io (fd => IO::AIO::poll_fileno, |
|
|
1225 | poll => 'r', |
|
|
1226 | cb => \&IO::AIO::poll_cb); |
|
|
1227 | |
|
|
1228 | # Glib/Gtk2 integration |
|
|
1229 | add_watch Glib::IO IO::AIO::poll_fileno, |
|
|
1230 | in => sub { IO::AIO::poll_cb; 1 }; |
|
|
1231 | |
|
|
1232 | # Tk integration |
|
|
1233 | Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "", |
|
|
1234 | readable => \&IO::AIO::poll_cb); |
|
|
1235 | |
|
|
1236 | # Danga::Socket integration |
|
|
1237 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
|
|
1238 | \&IO::AIO::poll_cb); |
825 | |
1239 | |
826 | FORK BEHAVIOUR |
1240 | FORK BEHAVIOUR |
827 | This module should do "the right thing" when the process using it forks: |
1241 | This module should do "the right thing" when the process using it forks: |
828 | |
1242 | |
829 | Before the fork, IO::AIO enters a quiescent state where no requests can |
1243 | Before the fork, IO::AIO enters a quiescent state where no requests can |
… | |
… | |
845 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
1259 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
846 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
1260 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
847 | scalars and other data passed into aio requests will also be locked and |
1261 | scalars and other data passed into aio requests will also be locked and |
848 | will consume memory till the request has entered the done state. |
1262 | will consume memory till the request has entered the done state. |
849 | |
1263 | |
850 | This is now awfully much, so queuing lots of requests is not usually a |
1264 | This is not awfully much, so queuing lots of requests is not usually a |
851 | problem. |
1265 | problem. |
852 | |
1266 | |
853 | Per-thread usage: |
1267 | Per-thread usage: |
854 | |
1268 | |
855 | In the execution phase, some aio requests require more memory for |
1269 | In the execution phase, some aio requests require more memory for |
… | |
… | |
858 | |
1272 | |
859 | KNOWN BUGS |
1273 | KNOWN BUGS |
860 | Known bugs will be fixed in the next release. |
1274 | Known bugs will be fixed in the next release. |
861 | |
1275 | |
862 | SEE ALSO |
1276 | SEE ALSO |
863 | Coro::AIO. |
1277 | AnyEvent::AIO for easy integration into event loops, Coro::AIO for a |
|
|
1278 | more natural syntax. |
864 | |
1279 | |
865 | AUTHOR |
1280 | AUTHOR |
866 | Marc Lehmann <schmorp@schmorp.de> |
1281 | Marc Lehmann <schmorp@schmorp.de> |
867 | http://home.schmorp.de/ |
1282 | http://home.schmorp.de/ |
868 | |
1283 | |