[ViewVC] Contents of: cvs/IO-AIO/Changes

Revision history for IO::AIO

TODO: better autoconf.pm that can return LIBS etc.
TODO: aio_cptree/mvtree
TODO: reduce condvar fairness: schedule hot-cache-threads first?
TODO: splice/tee/vmsplice? (http://kerneltrap.org/node/6505 http://lwn.net/Articles/178199/)
TODO: aio_fcntl, at least for file-locking
TODO: fallocate, if it wouldn't be so useless.

        - fix result status documentation of aio_copy, aio_move.
        - speed up object creation considerably by avoiding
          hash lookups.

3.3  Wed Aug  5 13:52:58 CEST 2009
        - use common::sense.
        - use common schmorp.h header.
        - allow integers (file descriptors) in addition to file handles.
        - take advantage of linux' eventfd (but it seems slower on smp?).
        - use poll not select on posix platforms.

3.261 Wed Jul  1 10:11:51 CEST 2009
        - more 0S X workarounds (patch by Tokuhiro Matsuno).

3.26 Tue Jun 30 09:33:26 CEST 2009
        - 0S X of course claims to be posix 2008 but lacks posix_fadvise.
          try to work around this horribly broken OS in a somewhat hackish
          way. might help other os's too.

3.25 Sat Jun 27 05:18:26 CEST 2009
        - added IO::AIO::fadvise and IO::AIO::sendfile.
        - (libeio) replaced quicksort+insertion sort by a tuned radix
          sort + insertion sort, resulting in comparable runtime (usually
          faster) to the old version, but without any ill side effects on
          degenerated (for quicksort) data.
        - (libeio) correctly sort dirs by inodes if we have perfect type
          knowledge and DIRS_FIRST is used.
        - (libeio) internally the wrong DT_* constants were used, but no
          known system has differing EIO_DT_*/DT_* values, so not an issue.
        - removed a (harmless) assert that was left over on the code
          but should not have been.
        - use more correct types (change IO length from IV to VAL64,
          which makes a difference on systems without 64 bit perls).

3.23 Sat Jun 13 16:57:58 CEST 2009
        - fix off-by-one bug in aio_readdir that was introduced in the
          rushed 3.22 release.

3.22 Sat Jun 13 15:32:40 CEST 2009
        - speed up readdirx sort algorithm slightly.
        - bin/treescan was missing from distro tarball.

3.21 Fri Jun 12 18:45:53 CEST 2009
        - new options --dirs and --files for treescan.
        - install bin/treescan by default.
        - (libeio) aio_readdir can now be cancelled while executing.
        - fix a printf format string for 64 bit systems (could lead
          to problems on big endian 64 bit systems).
        - do not use qsort() but our own algorithm: glibc initialises
          the whole locale and I/O subsystem inside qsort, causing
          a stack overflow on 32 bit machines. The new sort uses much less
          stack and is more than twice as fast in typical situations.

3.2  Sun Jun  7 20:30:05 CEST 2009
        - (libeio) pwrite emulation was even more flawed than intended and did
          not restore the file offset.
        - add aio_readdirx, which can return inode and filetype and sort
          the names in various ways.
        - unfortunately, utime, chmod, chown on an open file that has just
          been written can easily block, which caused aio_copy to block the
          process. no more!
        - no longer rely on dst path in aio_copy when futime is available.

3.19 Tue Apr 21 22:05:21 CEST 2009
        - more perl 5.10 workarounds for aio_read and write.
        - aio_write no longer modifies the sv (if possible).
        - aio_read now works correctly with magic values.

3.18 Sun Apr 19 21:17:32 CEST 2009
        - better diagnostics when some aio_* functions get passed an illegal fh.
        - try to avoid crashes due to incompatible 5.10 API changes. grmbl.

3.17 Thu Nov 20 08:45:36 CET 2008
        - (libeio) added aio_sync_file_range (untested).
        - add aio_busy to @IO::AIO::AIO_REQ.

3.16 Wed Oct 22 18:28:01 CEST 2008
        - use SvREFCNT_inc instead of SvREFCNT_inc_NN in a non-speed critical
          part to improve portability to perl 5.8 (reported by szymon).

3.15 Mon Oct 13 00:39:55 CEST 2008
        - automatic removal of feeders was broken.
        - (libeio) use a more robust method to detect whether a feeder
          has added something to the group or not.

3.1  Thu Oct  2 13:34:40 CEST 2008
        - pre-deref the passed callback object, for increased speed
          and decreased memory usage.
        - call on_next_submit callback even for aio_group - impact unknown,
          but seems more correct.
        - $req->cb now returns the original callback.
        - (libeio) pass EIO_GROUP/aio_group requests through the queue without
          requiring a thread switch.
        - (libeio) status code of aio_futime and aio_utime was always passed 0.
        - do some other µ-optimisations.

3.07 Sat Aug  2 16:06:13 CEST 2008
        - do not include LIBS in autoconf tests.

3.06 Tue Jul 15 12:41:32 CEST 2008
        - move preadwritelock definition before it's first reference,
          to make it compile again on broken platforms (they still exist)
          or badly cofngiured perls (redhat...), reported by Rob Bloodgood.

3.05 Thu Jun 19 23:23:52 CEST 2008
        - work around perl overriding readdir etc. with thread-unsafe
          (sic!) versions.

3.04 Wed Jun 18 01:35:38 CEST 2008
        - (libeio) fix eio_mknod, which confused it's arguments.
        - (libeio) do not use readdir_r, as Ulrich Drepper pointed out that this
          is stupid.
        - (libeio) fix eio__readahead prototype, patch by Jost Krieger.
        - (libeio) fix a bug that could potentially cause IO::AIO
          not to get initialised properly.

3.03 Thu May 29 05:33:30 CEST 2008
        - (libeio) correctly call pthread_attr_destroy ().
        - (libeio) work around broken bsd headers once more.
        - reduce shared library size again by not including wrappers.
        - max_outstanding could cause poll to enter a busy-waiting loop.
        - document the new IO::AIO::poll_cb result value.

3.02 Mon May 12 02:32:02 CEST 2008
        - fix a memory leak on aio_readlink.
        - bring back working fchmod.
        - nop and busy now set result to 0.
        - set errno to ENOMEM when allocation fails.

3.01 Sun May 11 03:07:03 CEST 2008
        - (libeio) make it compile on systems without readahead or readdir_r.
        - (libeio) improve configure check for readahead availability.
        - do not try to link against -lrt.
        - use a separate configure script for IO::AIO (not the libeio one).

3.0  Sun May 11 00:57:14 CEST 2008
        - added bin/treescan to the distribution.
        - switched to using libeio.
        - LOTS OF INCOMPATIBLE CHANGES:
          - remove signal functionality, it is not worth the effort.
          - max_outstanding no longer returns the previous number of requests.
          - poll_cb no longer returns number of requests.

2.62 Sat Apr 26 13:59:33 CEST 2008
        - port to solaris perls configured for old posix
          (analysed by Jost Krieger).
        - keep a reference to the perl filehandle object in aio_close,
          so it doesn't get closed prematurely, leading to ugly races.

2.61 Wed Apr 16 18:45:02 CEST 2008
        - fix treescan output duplication and improve output ordering.
          also display files given on the commandline.
        - use a different algorithm for aio_close that is faster
          and probably has even lower chances of blocking.
        - do our own stack memory management for threads - linux
          allocates outrageous amounts of VM (not so bad unless you
          use mlockall...), which severely limits the number of threads
          on 32-bit arches: stack size is the larger of PTHREAD_STACK_MIN
          and 4096 * sizeof (long) (usually this is 16..64k).

2.6  Sun Mar 30 08:28:11 CEST 2008
        - added aio_sync.
        - added aio_pathsync.
        - fix prototypes of (void) functions.

2.51 Sat Oct  6 16:04:54 CEST 2007
        - perlio isn't generally threadsafe, so aio_close could not work reliably.
          aio_close now tries a safe hack that might not be that asynchronous
          (see the manpage for details).
        - discard callback return values as to not grow the stack endlessly
          when poll_cb handles many requests without returning.
        - minor code cleanups.

2.5  Thu Oct  4 14:49:08 CEST 2007
        - replaced _fd2fh with faster xs code.
        - aio_close will now try to do "the right thing" and thus might
          work sensibly for the very first time.

2.41 Mon Sep 24 21:28:21 CEST 2007
        - after fork, invest some work to make sure that the poll_fileno
          stays stable (by dup2'ing the new fd over the old one), to make
          it easier for programs/libs that don't control their forking
          behaviour and cannot recreate their watchers.

2.4  Sun Aug  5 18:44:22 CEST 2007
        - add aio_truncate, aio_chmod, aio_chown, aio_utime (linux
          successfully demonstrated that you can block on futimes...).
        - allow undef as fileoffset for aio_read/write and use read/write(2)
          internally (useful for sockets or O_APPEND handles).
        - allow undef for length in aio_write.
        - negative dataoffsets work as expected now in aio_read/aio_write.
        - use NV instead of UV for 32 bit perls and file offsets, as NVs
          have a larger range then.
        - shared code between BDB and IO::AIO.
        - aio_busy was completely broken. now fixed.
        - readahead emulation now returns something.
        - correctly set errno to ENOSYS on unimplemented functions
          (should never happen, though).
        - large changes to make it partially compile and run on win32,
          but win32 lacks too much functionality, and perl overrides way
          too many functions with crashing versions.

2.33 Tue Jan 23 23:55:41 CET 2007
        - fix install path (Andreas J. Koenig).

2.32 Mon Jan 22 16:56:23 CET 2007
        - added aio_rmtree.
        - wow, aio_mkdir was missing.
        - aio_load did return undef on error, not -1.
        - use prefixexp not prefix in autoconf.pm
          (suggested by ... rt.cpan.org unreachable).
        - avoid installing autoconf.pm.

2.31 Sat Jan  6 03:46:02 CET 2007
        - added aio_load.

2.3  Sat Dec 23 05:48:07 CET 2006
        - fix off-by-one bug in aio_read, causing memory corruption
          or crashes.

2.21  Fri Dec 22 05:03:38 CET 2006
        - minor doc updates.
        - minor cleanups.
        - IO::AIO::poll returns request count.
        - undocumented and unfinished async-signal-reporting.

2.2  Tue Oct 31 00:31:00 CET 2006
        - minor doc updates.
        - added aio_readlink.
        - properly zero-terminate aio_read buffer.
        - fix aio_read/write with nonzero dataoffset.
        - reduced size of aio request structure.
        - better diagnostics when pathnames etc. are not byte-encoded;
          do not leak request in that case, either.

2.1  Sun Oct 29 02:01:57 CET 2006
        - INCOMPATIBLE CHANGE: replace IO::AIO::poll_some by
          IO::AIO::max_poll_reqs and IO::AIO::max_poll_time.
        - fix a bug in aio_move where it would fail everytime
          it would have to copy files manually.
        - doc updates.
        - start threads only on (very low) demand.
        - end superfluous threads automatically after 10s idling.
        - add IO::AIO::max_idle to control this.
        - some tuning applied to random places.
        - add aio_mknod.

2.0  Thu Oct 26 18:27:58 CEST 2006
        - minor incompatibility: max_outstanding semantics have changed.
        - major rewrite, consider all functionality EXPERIMENTAL.
        - aio requests can be cancelled.
        - callbacks can be (re-)set later.
        - aio requests can choose between 9 priorities.
        - add aio_group: aio requests can be grouped
          into composite requests.
        - generator interface for groups.
        - add IO::AIO::poll_some.
        - major documentation improvements.
        - very minor bugfixes.
        - add aio_nop for dummy requests.
        - add aio_busy mainly for benchmarking and debugging.
        - use "fast" mutexes on linux.
        - use dynamic (and larger) buffers instead of
          putting them onto the stack.
        - optimise x86 and amd64 a bit.
        - better error checking when ENOMEM.
        - hopefully fix mem and dirp leaks on fork.
        - warn about broken perl malloc.
        - compiles on cygwin (but pread is broken on cygwin
          which is not detected by autoconf, so you have to
          edit autoconf/config.h yourself to enable emulation).

1.8  Sat Jun 24 22:20:44 CEST 2006
        - add and/or document aio_rename, aio_link, aio_symlink and aio_move.

1.73 Wed Mar  1 22:49:32 CET 2006
        - codename "jost"
        - AIX/Solaris(?) aren't being helpful again, hardcode a value
          for NAME_MAX and drive with your eyes closed (reported by
          wcooley@nakedape.cc).

1.72 Thu Feb  2 00:40:44 CET 2006
        - another minor bug in aio_scandir, again, the callback was called
          twice when the directory can't be stat'ed.

1.71 Mon Dec 26 20:20:03 CET 2005
        - grr, another minor bug in aio_scandir, this time resulting
          in a runtime error.

1.7  Mon Dec 26 19:29:48 CET 2005
        - aio_scandir errornously called callback twice in some cases.
        - added AnyEvent example.

1.61 Wed Sep  7 19:40:42 CEST 2005
        - no longer include $Config{libs}, as distros include too much
          garbage in there that is not installed on typical systems
          (for example, debian links perl against -lgdbm and many more
          libraries despite perl not needing it, slowing down startup and
          wasting memory).

1.6  Tue Aug 30 17:44:44 CEST 2005
        - added aio_readdir, aio_scandir.
        - added aio_sendfile, including sendfile emulation when sendfile
          isn't available. Linux, FreeBSD and HP-UX might work (sendfilev
          support is unavailable on my solaris 8 machine, but preliminary
          code is there. What's lacking is configury stuff and testing...).

1.5  Sat Aug 20 02:32:19 CEST 2005
        - create the aio threads on demand only (good after forking).
        - somebody nagged about C89 compatibility, so this release should
          be C89 compatible, but no guarantees for future ones.
        - abort when the configure script fails.

1.4  Wed Aug 17 08:07:27 CEST 2005
        - forgot to recreate the pipe after forking, this could cause
          deadlocks.

1.3  Wed Aug 17 07:25:54 CEST 2005
        - properly propagate exceptions from callbacks, instead of silently
          eating them.
        - use a different fork algorithm that avoids recursive callback
          invocations and reduces fork latency in busy processes.
        - fix a bug where the buffer scalar in aio_read got assigned the wrong
          length after reading.
        - fix a bug where the child would process some outstanding requests
          from the parent.
        - make a copy of the callback scalar, to avoid some very uncommon
          (but valid) usages where the callback scalar changes.
        - the callback was never freed in aio_read/aio_write.
        - aio_read/aio_write will now set the readonly flag on the data
          scalar for better error reporting.

1.2  Wed Aug 17 01:22:58 CEST 2005
        - verified on cygwin, linux/amd64+ia32+alpha, solaris.
        - use SvPVbyte for filenames now. You *need* to encode your strings to
          the external filename encoding first.
        - fix the bug where filehandles could leak (again).
        - clarify freebsd situation: make it work and tell me how, or go away
          with your underdocumented, broken and outdated OS.
        - fork'ing should now be officially supported (where linux and
          posix contradict each other, I followed posix).
        - only call read() once per poll, not twice (speedup).
        - new functions: aio_rmdir, aio_symlink.
        - force callback arguments to be undef or a reference, for better
          error catching.

1.1  Sun Aug  7 05:27:23 CEST 2005
        - added configure script to detect availability of some calls.
          (imperfect, as we cannot detect things like -lrt due to missing
          feedback yet).
        - emulate fdatasync via fsync, pread/pwrite via unsafe read/write
          and readahead via manual reading on platforms lacking those.
        - ported t/03_errors.t+framework by Brad Fitzpatrick
          from Linux::AIO.
        - removed XOPEN_SOURCE because stupid solaris 9 doesn't
          compile with it enabled. Probably breaks others. Oh well.
        - try to be more careful with errno on non-threaded perls.
        - cygwins perl insisted on a matching open mode when morphing
          the fd to an fh.
        - convert sv's to "byte" encoding in aio_read/aio_write. Might
          do that for pathnames, too, in the future, so make sure you
          properly encode your pathnames.

1.0  Fri Jul 22 10:43:30 CEST 2005
        - aio_open did not reliably deliver (open) filehandles.
        - all aio_*-functions keep a reference to the filehandle so
          it doesn't go away while the aio requests is working on it.
        - disable warnings in AIO.pm.

0.9  Wed Jul 20 23:55:04 CEST 2005
        - allow recursive calls to poll_cb, use less locking calls, too.
        - fix the Gtk2-example in the SYNOPSIS.
        - use pread/pwrite not pread64/pwrite64. this was simply a leftover
          from Linux::AIO.
          (found by compiling on cygwin. Unfortunately, cygwin declares but
          does not implement pread/pwrite).
        - only include <sys/syscall.h> on linux.

0.5  Tue Jul 12 13:03:09 CEST 2005
        - removed #include <endian.h>, it's not portable, and we don't
          need it anyway.
        - link against -lrt, as it might contain goodies such as fdatasync,
          and often aio_read, which we do not use yet, but it shouldn't hurt.

0.4  Mon Jul 11 05:28:25 CEST 2005
        - added IO::AIO::flush, IO::AIO::poll.
        - make callback argument optional for all calls.

0.3  Mon Jul 11 01:42:37 CEST 2005
        - restructured manpage.
        - added SYNOPSIS with examples for Event, Glib, Tk.
        - remove explicit context support so I don't have to maintain
          it for threaded perls (i.e. it should work now :).

0.2  Sun Jul 10 22:57:12 CEST 2005
        - return immediately from poll_wait if nreqs==0.
        - get rid of the request pipe and use faster thread-thread
          communications for most requests and responses.

0.1
        - cloned from Linux::AIO, which is very similar.

Revision:	1.207
Committed:	Thu Nov 12 00:01:52 2009 UTC (14 years, 6 months ago) by root
Branch:	MAIN
Changes since 1.206:	+6 -4 lines
Log Message:	* empty log message *
#	Content
1	Revision history for IO::AIO
2
3	TODO: better autoconf.pm that can return LIBS etc.
4	TODO: aio_cptree/mvtree
5	TODO: reduce condvar fairness: schedule hot-cache-threads first?
6	TODO: splice/tee/vmsplice? (http://kerneltrap.org/node/6505 http://lwn.net/Articles/178199/)
7	TODO: aio_fcntl, at least for file-locking
8	TODO: fallocate, if it wouldn't be so useless.
9
10	- fix result status documentation of aio_copy, aio_move.
11	- speed up object creation considerably by avoiding
12	hash lookups.
13
14	3.3 Wed Aug 5 13:52:58 CEST 2009
15	- use common::sense.
16	- use common schmorp.h header.
17	- allow integers (file descriptors) in addition to file handles.
18	- take advantage of linux' eventfd (but it seems slower on smp?).
19	- use poll not select on posix platforms.
20
21	3.261 Wed Jul 1 10:11:51 CEST 2009
22	- more 0S X workarounds (patch by Tokuhiro Matsuno).
23
24	3.26 Tue Jun 30 09:33:26 CEST 2009
25	- 0S X of course claims to be posix 2008 but lacks posix_fadvise.
26	try to work around this horribly broken OS in a somewhat hackish
27	way. might help other os's too.
28
29	3.25 Sat Jun 27 05:18:26 CEST 2009
30	- added IO::AIO::fadvise and IO::AIO::sendfile.
31	- (libeio) replaced quicksort+insertion sort by a tuned radix
32	sort + insertion sort, resulting in comparable runtime (usually
33	faster) to the old version, but without any ill side effects on
34	degenerated (for quicksort) data.
35	- (libeio) correctly sort dirs by inodes if we have perfect type
36	knowledge and DIRS_FIRST is used.
37	- (libeio) internally the wrong DT_* constants were used, but no
38	known system has differing EIO_DT_/DT_ values, so not an issue.
39	- removed a (harmless) assert that was left over on the code
40	but should not have been.
41	- use more correct types (change IO length from IV to VAL64,
42	which makes a difference on systems without 64 bit perls).
43
44	3.23 Sat Jun 13 16:57:58 CEST 2009
45	- fix off-by-one bug in aio_readdir that was introduced in the
46	rushed 3.22 release.
47
48	3.22 Sat Jun 13 15:32:40 CEST 2009
49	- speed up readdirx sort algorithm slightly.
50	- bin/treescan was missing from distro tarball.
51
52	3.21 Fri Jun 12 18:45:53 CEST 2009
53	- new options --dirs and --files for treescan.
54	- install bin/treescan by default.
55	- (libeio) aio_readdir can now be cancelled while executing.
56	- fix a printf format string for 64 bit systems (could lead
57	to problems on big endian 64 bit systems).
58	- do not use qsort() but our own algorithm: glibc initialises
59	the whole locale and I/O subsystem inside qsort, causing
60	a stack overflow on 32 bit machines. The new sort uses much less
61	stack and is more than twice as fast in typical situations.
62
63	3.2 Sun Jun 7 20:30:05 CEST 2009
64	- (libeio) pwrite emulation was even more flawed than intended and did
65	not restore the file offset.
66	- add aio_readdirx, which can return inode and filetype and sort
67	the names in various ways.
68	- unfortunately, utime, chmod, chown on an open file that has just
69	been written can easily block, which caused aio_copy to block the
70	process. no more!
71	- no longer rely on dst path in aio_copy when futime is available.
72
73	3.19 Tue Apr 21 22:05:21 CEST 2009
74	- more perl 5.10 workarounds for aio_read and write.
75	- aio_write no longer modifies the sv (if possible).
76	- aio_read now works correctly with magic values.
77
78	3.18 Sun Apr 19 21:17:32 CEST 2009
79	- better diagnostics when some aio_* functions get passed an illegal fh.
80	- try to avoid crashes due to incompatible 5.10 API changes. grmbl.
81
82	3.17 Thu Nov 20 08:45:36 CET 2008
83	- (libeio) added aio_sync_file_range (untested).
84	- add aio_busy to @IO::AIO::AIO_REQ.
85
86	3.16 Wed Oct 22 18:28:01 CEST 2008
87	- use SvREFCNT_inc instead of SvREFCNT_inc_NN in a non-speed critical
88	part to improve portability to perl 5.8 (reported by szymon).
89
90	3.15 Mon Oct 13 00:39:55 CEST 2008
91	- automatic removal of feeders was broken.
92	- (libeio) use a more robust method to detect whether a feeder
93	has added something to the group or not.
94
95	3.1 Thu Oct 2 13:34:40 CEST 2008
96	- pre-deref the passed callback object, for increased speed
97	and decreased memory usage.
98	- call on_next_submit callback even for aio_group - impact unknown,
99	but seems more correct.
100	- $req->cb now returns the original callback.
101	- (libeio) pass EIO_GROUP/aio_group requests through the queue without
102	requiring a thread switch.
103	- (libeio) status code of aio_futime and aio_utime was always passed 0.
104	- do some other µ-optimisations.
105
106	3.07 Sat Aug 2 16:06:13 CEST 2008
107	- do not include LIBS in autoconf tests.
108
109	3.06 Tue Jul 15 12:41:32 CEST 2008
110	- move preadwritelock definition before it's first reference,
111	to make it compile again on broken platforms (they still exist)
112	or badly cofngiured perls (redhat...), reported by Rob Bloodgood.
113
114	3.05 Thu Jun 19 23:23:52 CEST 2008
115	- work around perl overriding readdir etc. with thread-unsafe
116	(sic!) versions.
117
118	3.04 Wed Jun 18 01:35:38 CEST 2008
119	- (libeio) fix eio_mknod, which confused it's arguments.
120	- (libeio) do not use readdir_r, as Ulrich Drepper pointed out that this
121	is stupid.
122	- (libeio) fix eio__readahead prototype, patch by Jost Krieger.
123	- (libeio) fix a bug that could potentially cause IO::AIO
124	not to get initialised properly.
125
126	3.03 Thu May 29 05:33:30 CEST 2008
127	- (libeio) correctly call pthread_attr_destroy ().
128	- (libeio) work around broken bsd headers once more.
129	- reduce shared library size again by not including wrappers.
130	- max_outstanding could cause poll to enter a busy-waiting loop.
131	- document the new IO::AIO::poll_cb result value.
132
133	3.02 Mon May 12 02:32:02 CEST 2008
134	- fix a memory leak on aio_readlink.
135	- bring back working fchmod.
136	- nop and busy now set result to 0.
137	- set errno to ENOMEM when allocation fails.
138
139	3.01 Sun May 11 03:07:03 CEST 2008
140	- (libeio) make it compile on systems without readahead or readdir_r.
141	- (libeio) improve configure check for readahead availability.
142	- do not try to link against -lrt.
143	- use a separate configure script for IO::AIO (not the libeio one).
144
145	3.0 Sun May 11 00:57:14 CEST 2008
146	- added bin/treescan to the distribution.
147	- switched to using libeio.
148	- LOTS OF INCOMPATIBLE CHANGES:
149	- remove signal functionality, it is not worth the effort.
150	- max_outstanding no longer returns the previous number of requests.
151	- poll_cb no longer returns number of requests.
152
153	2.62 Sat Apr 26 13:59:33 CEST 2008
154	- port to solaris perls configured for old posix
155	(analysed by Jost Krieger).
156	- keep a reference to the perl filehandle object in aio_close,
157	so it doesn't get closed prematurely, leading to ugly races.
158
159	2.61 Wed Apr 16 18:45:02 CEST 2008
160	- fix treescan output duplication and improve output ordering.
161	also display files given on the commandline.
162	- use a different algorithm for aio_close that is faster
163	and probably has even lower chances of blocking.
164	- do our own stack memory management for threads - linux
165	allocates outrageous amounts of VM (not so bad unless you
166	use mlockall...), which severely limits the number of threads
167	on 32-bit arches: stack size is the larger of PTHREAD_STACK_MIN
168	and 4096 * sizeof (long) (usually this is 16..64k).
169
170	2.6 Sun Mar 30 08:28:11 CEST 2008
171	- added aio_sync.
172	- added aio_pathsync.
173	- fix prototypes of (void) functions.
174
175	2.51 Sat Oct 6 16:04:54 CEST 2007
176	- perlio isn't generally threadsafe, so aio_close could not work reliably.
177	aio_close now tries a safe hack that might not be that asynchronous
178	(see the manpage for details).
179	- discard callback return values as to not grow the stack endlessly
180	when poll_cb handles many requests without returning.
181	- minor code cleanups.
182
183	2.5 Thu Oct 4 14:49:08 CEST 2007
184	- replaced _fd2fh with faster xs code.
185	- aio_close will now try to do "the right thing" and thus might
186	work sensibly for the very first time.
187
188	2.41 Mon Sep 24 21:28:21 CEST 2007
189	- after fork, invest some work to make sure that the poll_fileno
190	stays stable (by dup2'ing the new fd over the old one), to make
191	it easier for programs/libs that don't control their forking
192	behaviour and cannot recreate their watchers.
193
194	2.4 Sun Aug 5 18:44:22 CEST 2007
195	- add aio_truncate, aio_chmod, aio_chown, aio_utime (linux
196	successfully demonstrated that you can block on futimes...).
197	- allow undef as fileoffset for aio_read/write and use read/write(2)
198	internally (useful for sockets or O_APPEND handles).
199	- allow undef for length in aio_write.
200	- negative dataoffsets work as expected now in aio_read/aio_write.
201	- use NV instead of UV for 32 bit perls and file offsets, as NVs
202	have a larger range then.
203	- shared code between BDB and IO::AIO.
204	- aio_busy was completely broken. now fixed.
205	- readahead emulation now returns something.
206	- correctly set errno to ENOSYS on unimplemented functions
207	(should never happen, though).
208	- large changes to make it partially compile and run on win32,
209	but win32 lacks too much functionality, and perl overrides way
210	too many functions with crashing versions.
211
212	2.33 Tue Jan 23 23:55:41 CET 2007
213	- fix install path (Andreas J. Koenig).
214
215	2.32 Mon Jan 22 16:56:23 CET 2007
216	- added aio_rmtree.
217	- wow, aio_mkdir was missing.
218	- aio_load did return undef on error, not -1.
219	- use prefixexp not prefix in autoconf.pm
220	(suggested by ... rt.cpan.org unreachable).
221	- avoid installing autoconf.pm.
222
223	2.31 Sat Jan 6 03:46:02 CET 2007
224	- added aio_load.
225
226	2.3 Sat Dec 23 05:48:07 CET 2006
227	- fix off-by-one bug in aio_read, causing memory corruption
228	or crashes.
229
230	2.21 Fri Dec 22 05:03:38 CET 2006
231	- minor doc updates.
232	- minor cleanups.
233	- IO::AIO::poll returns request count.
234	- undocumented and unfinished async-signal-reporting.
235
236	2.2 Tue Oct 31 00:31:00 CET 2006
237	- minor doc updates.
238	- added aio_readlink.
239	- properly zero-terminate aio_read buffer.
240	- fix aio_read/write with nonzero dataoffset.
241	- reduced size of aio request structure.
242	- better diagnostics when pathnames etc. are not byte-encoded;
243	do not leak request in that case, either.
244
245	2.1 Sun Oct 29 02:01:57 CET 2006
246	- INCOMPATIBLE CHANGE: replace IO::AIO::poll_some by
247	IO::AIO::max_poll_reqs and IO::AIO::max_poll_time.
248	- fix a bug in aio_move where it would fail everytime
249	it would have to copy files manually.
250	- doc updates.
251	- start threads only on (very low) demand.
252	- end superfluous threads automatically after 10s idling.
253	- add IO::AIO::max_idle to control this.
254	- some tuning applied to random places.
255	- add aio_mknod.
256
257	2.0 Thu Oct 26 18:27:58 CEST 2006
258	- minor incompatibility: max_outstanding semantics have changed.
259	- major rewrite, consider all functionality EXPERIMENTAL.
260	- aio requests can be cancelled.
261	- callbacks can be (re-)set later.
262	- aio requests can choose between 9 priorities.
263	- add aio_group: aio requests can be grouped
264	into composite requests.
265	- generator interface for groups.
266	- add IO::AIO::poll_some.
267	- major documentation improvements.
268	- very minor bugfixes.
269	- add aio_nop for dummy requests.
270	- add aio_busy mainly for benchmarking and debugging.
271	- use "fast" mutexes on linux.
272	- use dynamic (and larger) buffers instead of
273	putting them onto the stack.
274	- optimise x86 and amd64 a bit.
275	- better error checking when ENOMEM.
276	- hopefully fix mem and dirp leaks on fork.
277	- warn about broken perl malloc.
278	- compiles on cygwin (but pread is broken on cygwin
279	which is not detected by autoconf, so you have to
280	edit autoconf/config.h yourself to enable emulation).
281
282	1.8 Sat Jun 24 22:20:44 CEST 2006
283	- add and/or document aio_rename, aio_link, aio_symlink and aio_move.
284
285	1.73 Wed Mar 1 22:49:32 CET 2006
286	- codename "jost"
287	- AIX/Solaris(?) aren't being helpful again, hardcode a value
288	for NAME_MAX and drive with your eyes closed (reported by
289	wcooley@nakedape.cc).
290
291	1.72 Thu Feb 2 00:40:44 CET 2006
292	- another minor bug in aio_scandir, again, the callback was called
293	twice when the directory can't be stat'ed.
294
295	1.71 Mon Dec 26 20:20:03 CET 2005
296	- grr, another minor bug in aio_scandir, this time resulting
297	in a runtime error.
298
299	1.7 Mon Dec 26 19:29:48 CET 2005
300	- aio_scandir errornously called callback twice in some cases.
301	- added AnyEvent example.
302
303	1.61 Wed Sep 7 19:40:42 CEST 2005
304	- no longer include $Config{libs}, as distros include too much
305	garbage in there that is not installed on typical systems
306	(for example, debian links perl against -lgdbm and many more
307	libraries despite perl not needing it, slowing down startup and
308	wasting memory).
309
310	1.6 Tue Aug 30 17:44:44 CEST 2005
311	- added aio_readdir, aio_scandir.
312	- added aio_sendfile, including sendfile emulation when sendfile
313	isn't available. Linux, FreeBSD and HP-UX might work (sendfilev
314	support is unavailable on my solaris 8 machine, but preliminary
315	code is there. What's lacking is configury stuff and testing...).
316
317	1.5 Sat Aug 20 02:32:19 CEST 2005
318	- create the aio threads on demand only (good after forking).
319	- somebody nagged about C89 compatibility, so this release should
320	be C89 compatible, but no guarantees for future ones.
321	- abort when the configure script fails.
322
323	1.4 Wed Aug 17 08:07:27 CEST 2005
324	- forgot to recreate the pipe after forking, this could cause
325	deadlocks.
326
327	1.3 Wed Aug 17 07:25:54 CEST 2005
328	- properly propagate exceptions from callbacks, instead of silently
329	eating them.
330	- use a different fork algorithm that avoids recursive callback
331	invocations and reduces fork latency in busy processes.
332	- fix a bug where the buffer scalar in aio_read got assigned the wrong
333	length after reading.
334	- fix a bug where the child would process some outstanding requests
335	from the parent.
336	- make a copy of the callback scalar, to avoid some very uncommon
337	(but valid) usages where the callback scalar changes.
338	- the callback was never freed in aio_read/aio_write.
339	- aio_read/aio_write will now set the readonly flag on the data
340	scalar for better error reporting.
341
342	1.2 Wed Aug 17 01:22:58 CEST 2005
343	- verified on cygwin, linux/amd64+ia32+alpha, solaris.
344	- use SvPVbyte for filenames now. You need to encode your strings to
345	the external filename encoding first.
346	- fix the bug where filehandles could leak (again).
347	- clarify freebsd situation: make it work and tell me how, or go away
348	with your underdocumented, broken and outdated OS.
349	- fork'ing should now be officially supported (where linux and
350	posix contradict each other, I followed posix).
351	- only call read() once per poll, not twice (speedup).
352	- new functions: aio_rmdir, aio_symlink.
353	- force callback arguments to be undef or a reference, for better
354	error catching.
355
356	1.1 Sun Aug 7 05:27:23 CEST 2005
357	- added configure script to detect availability of some calls.
358	(imperfect, as we cannot detect things like -lrt due to missing
359	feedback yet).
360	- emulate fdatasync via fsync, pread/pwrite via unsafe read/write
361	and readahead via manual reading on platforms lacking those.
362	- ported t/03_errors.t+framework by Brad Fitzpatrick
363	from Linux::AIO.
364	- removed XOPEN_SOURCE because stupid solaris 9 doesn't
365	compile with it enabled. Probably breaks others. Oh well.
366	- try to be more careful with errno on non-threaded perls.
367	- cygwins perl insisted on a matching open mode when morphing
368	the fd to an fh.
369	- convert sv's to "byte" encoding in aio_read/aio_write. Might
370	do that for pathnames, too, in the future, so make sure you
371	properly encode your pathnames.
372
373	1.0 Fri Jul 22 10:43:30 CEST 2005
374	- aio_open did not reliably deliver (open) filehandles.
375	- all aio_*-functions keep a reference to the filehandle so
376	it doesn't go away while the aio requests is working on it.
377	- disable warnings in AIO.pm.
378
379	0.9 Wed Jul 20 23:55:04 CEST 2005
380	- allow recursive calls to poll_cb, use less locking calls, too.
381	- fix the Gtk2-example in the SYNOPSIS.
382	- use pread/pwrite not pread64/pwrite64. this was simply a leftover
383	from Linux::AIO.
384	(found by compiling on cygwin. Unfortunately, cygwin declares but
385	does not implement pread/pwrite).
386	- only include <sys/syscall.h> on linux.
387
388	0.5 Tue Jul 12 13:03:09 CEST 2005
389	- removed #include <endian.h>, it's not portable, and we don't
390	need it anyway.
391	- link against -lrt, as it might contain goodies such as fdatasync,
392	and often aio_read, which we do not use yet, but it shouldn't hurt.
393
394	0.4 Mon Jul 11 05:28:25 CEST 2005
395	- added IO::AIO::flush, IO::AIO::poll.
396	- make callback argument optional for all calls.
397
398	0.3 Mon Jul 11 01:42:37 CEST 2005
399	- restructured manpage.
400	- added SYNOPSIS with examples for Event, Glib, Tk.
401	- remove explicit context support so I don't have to maintain
402	it for threaded perls (i.e. it should work now :).
403
404	0.2 Sun Jul 10 22:57:12 CEST 2005
405	- return immediately from poll_wait if nreqs==0.
406	- get rid of the request pipe and use faster thread-thread
407	communications for most requests and responses.
408
409	0.1
410	- cloned from Linux::AIO, which is very similar.
411