I looked a bit closer at your code and noticed that you add STDIN to your select call instead of readHandle. Any reason? It might be that this is your problem.

I tried the following test script and it works. I get output every 5 seconds:

#!/usr/bin/perl

use warnings;
use Data::Dumper;
use IO::Handle;
use IPC::Open2;
use IO::Select;

my $i;
my ($readHandle, $writeHandle) = (IO::Handle->new, IO::Handle->new);
my $pid = open2($readHandle, $writeHandle, 'bc');

$writeHandle->autoflush(1);
$readHandle->autoflush(1);

my $select = IO::Select->new();
$select->add($readHandle);
while (1) {
    print $i++,"\n";
    my ($handle) = $select->can_read(5);
}

[download]

Interestingly it works even when I turn off blocking, which means my previous notion that can_read would not wait if blocking is turned off might be false.

In reply to Re^5: Performance and CPU load: sysread, IO::Select and/or Storable::thaw by jethro
in thread Performance and CPU load: sysread, IO::Select and/or Storable::thaw by DBX

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