Perl modules dudes:
We are having big problems with this LIRAZ guy who still will
not release control over IO::Multiplex because he cannot be
contacted. He is not involved with this version of IO::Multiplex
either. Can you reassign cpan author from LIRAZ to BBB for me?
Or how can we fix this situation?
Douglas:
Looks fantastic. I'm reviewing your patch now. I've only been
able to get around 50 connections/sec because of some large CPU
overhead. I'm starting to maintain it a little more, but I'm
not the original author. Bruce is. I think your patch will help.
You should see it in version 1.04. I'll let him know, too.
Thanks,
Rob Brown
CPANID: BBB
On Thu, 30 May 2002, Douglas Webb wrote:
> I've been working on a project for my company which requires a daemon
> process to take in ~1 request/second from 1000 other processes on the
> same machine, and send those 1000 requests/sec through some parsing and
> then on to Oracle.
>
> The architecture I decided on was to have a single select-based process
> that would watch 1000 sockets for input, and to pass that input to 20 or
> so sockets which are connected to forked-off subprocesses. The
> subprocesses would handle the parsing and DBI stuff. This lets me spend
> a lot more time dealing with Oracle than I otherwise could.
>
> I looked in Network Programming with Perl, and figured that somebody
> must have already put the examples in there onto CPAN. That's how I
> found IO::Multiplex.
>
> Overall, I'm happy with IO::Multiplex; the testing I've done so far
> tells me that it'll be able to handle my needs reliably. However, I
> discovered that it uses way more cpu time than it needs to, due to the
> use of Tie::RefHash.
>
> That module lets you use a reference as a hash key, but pretend that
> it's still a reference. Normally, the reference is turned into a string,
> and the string is used as the key.
> When I ran my program through Devel::DProf, I found that a huge amount
> of time was being spent in FETCH, NEXTKEY, EXISTS in the Tie::RefHash
> module.
>
> After searching through IO::Multiplex, I found that there were only a
> couple of places where the hash keys are being used as references (to
> filehandles.) The rest of the accesses just used them as keys, so the
> Tie::RefHash was a waste. I added a new key to $self, _handles, to map
> from the stringified filehandle reference to the real filehandle
> reference, and I made a few other changes to use the new key only where
> needed. This gave me about a 20x reduction in the cpu usage under the
> same request/sec load.
>
> Here's the diff for my changes; there aren't many of them.
> I don't think there are any drawbacks to my approach.
>
> Let me know if you have any questions.
> Doug.
>
>
> bash-2.03$ diff -C 1 Multiplex.orig.pm Multiplex.doug.pm
> *** Multiplex.orig.pm Mon Feb 4 13:14:03 2002
> --- Multiplex.doug.pm Thu May 30 11:04:02 2002
> ***************
> *** 161,163 ****
> use IO::Multiplex;
> - use Tie::RefHash;
>
> --- 161,162 ----
> ***************
> *** 271,273 ****
> use Data::Dumper;
> - use Tie::RefHash;
> use Carp qw(cluck);
> --- 270,271 ----
> ***************
> *** 301,304 ****
> _fhs => {},
> _listen => {} } => $package;
> - tie %{$self->{_fhs}}, "Tie::RefHash";
> $self;
> --- 299,302 ----
> _fhs => {},
> + _handles => {},
> _listen => {} } => $package;
> $self;
> ***************
> *** 353,354 ****
> --- 351,353 ----
> $self->{_fhs}{$fh}{fileno} = fileno($fh);
> + $self->{_handles}{$fh} = $fh;
> tie *$fh, "MVModule::MVmux::Handle", $self, $fh;
> ***************
> *** 374,375 ****
> --- 373,375 ----
> delete $self->{_fhs}{$fh};
> + delete $self->{_handles}{$fh};
> untie *$fh;
> ***************
> *** 518,520 ****
>
> ! grep(!$self->{_fhs}{$_}{listen}, keys %{$self->{_fhs}});
> }
> --- 518,520 ----
>
> ! grep(!$self->{_fhs}{$_}{listen}, values %{$self->{_handles}});
> }
> ***************
> *** 563,565 ****
>
> ! foreach my $fh (keys %{$self->{_fhs}}) {
> # Avoid creating a permanent empty hash ref for "$fh"
> --- 563,565 ----
>
> ! foreach my $fh (values %{$self->{_handles}}) {
> # Avoid creating a permanent empty hash ref for "$fh"
> ***************
> *** 797,798 ****
> --- 797,799 ----
> delete $self->{_fhs}{$fh};
> + delete $self->{_handles}{$fh};
> untie *$fh;
> ***************
> *** 800,802 ****
> $obj->mux_close($self, $fh) if $obj && $obj->can("mux_close");
> - delete $self->{_fhs}{$fh};
> }
> --- 801,802 ----
>
>
>
>
