[ViewVC] Diff of: cvs/Coro/README

Comparing Coro/README (file contents):
Revision 1.23 by root, Fri May 29 07:01:18 2009 UTC vs.
Revision 1.24 by root, Tue Jun 23 23:40:06 2009 UTC

 NAME
     Coro - the only real threads in perl
 SYNOPSIS
       use Coro;
-  async {
+      async {
          # some asynchronous thread of execution
          print "2\n";
          cede; # yield back to main
          print "4\n";
       };
       print "1\n";
       cede; # yield to coro
       print "3\n";
       cede; # and again
-  # use locking
+      # use locking
       use Coro::Semaphore;
       my $lock = new Coro::Semaphore;
       my $locked;
-  $lock->down;
+      $lock->down;
       $locked = 1;
       $lock->up;
 DESCRIPTION
     For a tutorial-style introduction, please read the Coro::Intro manpage.
         These functions implement the same concept as "dynamic-wind" in
         scheme does, and are useful when you want to localise some resource
         to a specific coro.
-        They slow down coro switching considerably for coros that use them
+        They slow down thread switching considerably for coros that use them
+        (about 40% for a BLOCK with a single assignment, so thread switching
-        (But coro switching is still reasonably fast if the handlers are
+        is still reasonably fast if the handlers are fast).
-        fast).
         These functions are best understood by an example: The following
         function will change the current timezone to
         "Antarctica/South_Pole", which requires a call to "tzset", but by
         using "on_enter" and "on_leave", which remember/change the current
            };
         This can be used to localise about any resource (locale, uid,
         current working directory etc.) to a block, despite the existance of
         other coros.
+        Another interesting example implements time-sliced multitasking
+        using interval timers (this could obviously be optimised, but does
+        the job):
+           # "timeslice" the given block
+           sub timeslice(&) {
+              use Time::HiRes ();
+              Coro::on_enter {
+                 # on entering the thread, we set an VTALRM handler to cede
+                 $SIG{VTALRM} = sub { cede };
+                 # and then start the interval timer
+                 Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0.01, 0.01;
+              };
+              Coro::on_leave {
+                 # on leaving the thread, we stop the interval timer again
+                 Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0, 0;
+              };
+              &{+shift};
+           }
+           # use like this:
+           timeslice {
+              # The following is an endless loop that would normally
+              # monopolise the process. Since it runs in a timesliced
+              # environment, it will regularly cede to other threads.
+              while () { }
+           };
     killall
         Kills/terminates/cancels all coros except the currently running one.
         Note that while this will try to free some of the main interpreter

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Comparing Coro/README (file contents): Revision 1.23 by root, Fri May 29 07:01:18 2009 UTC vs. Revision 1.24 by root, Tue Jun 23 23:40:06 2009 UTC

Diff Legend

Comparing Coro/README (file contents):
Revision 1.23 by root, Fri May 29 07:01:18 2009 UTC vs.
Revision 1.24 by root, Tue Jun 23 23:40:06 2009 UTC