If your Perl apps are unusually slow on CentOS 5, have a look at this blog:
http://blog.vipul.net/2008/08/24/redhat-perl-what-a-tragedy/
In a nutshell: some Perl apps are 100x slower on RedHat / CentOS 5 compared to other distributions.
Bugzilla entry:
https://bugzilla.redhat.com/show_bug.cgi?id=379791
On Mon, Aug 25, 2008 at 1:30 PM, Florin Andrei florin@andrei.myip.org wrote:
Just forwarding a posting on the Scientifix Linux mailing list that is addressing the same perl issue and calling for collaborative effort with CentOS.
Akemi
======= forwarded message ======= Date: Tue, 26 Aug 2008 08:58:40 -0700 Sender: Mailling list for Scientific Linux users worldwide From: Keith Lofstrom Subject: Horribly Broken RHEL5/SL5 Perl Comments: To: Scientific Linux
This just in: http://blog.vipul.net/2008/08/24/redhat-perl-what-a-tragedy/
Summary: The Upstream Vendor version of Perl has a patch to the "bless[]" function that makes it /extremely/ slow. Most of us do not write that kind of of fancy Perl, but a lot of us use one of the 1500+ CPAN modules that do. The slowdown can be over 100x with some programs. This affects Fedora 9 as well as the various version 5 distros. TUV-patched Perl version 5.8.8 also breaks the Math::GSL package that I wrote about a few days ago. It runs fine with 5.10 . What to do? Some people are downloading and recompiling Perl; we have version 5.8.8, while version 5.10 is available . A few are abandoning Perl. A few are abandoning TUV-inspired distros. A few are buying way more hardware than they would otherwise need. Since some of the scientific community (especially the life sciences) are running huge amounts of Perl, this is probably a Big Deal. We should explore the problem further with TUV and the CentOS community. If a fix is not forthcoming from TUV, I reluctantly suggest that we get together with the CentOS people and fork this portion of the distro, perhaps standardizing on Perl 5.10 . There are people in the Perl community ready to assist us.
Keith -- Keith Lofstrom [log in to unmask] Voice (503)-520-1993 KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon" Design Contracting in Bipolar and CMOS - Analog, Digital, and Scan ICs
Akemi Yagi wrote:
Reliable info heard on the grapevine indicates 5.3 would have the fix's required.
On Tue, Aug 26, 2008 at 3:11 PM, Scott Silva ssilva@sgvwater.com wrote:
Unless upstream bundles a hotfix that is available for people...
hello,
--- On Tue, 8/26/08, Stephen John Smoogen smooge@gmail.com wrote:
Anyone want to try and get this built on C5.2? ftp://download.fedora.redhat.com/pub/fedora/linux/updates/8/SRPMS/perl-5.8.8-40.fc8.src.rpm
I've tested it out via the fc8 live CD and the bless/overload bug is absent.
------------- bug test ---------- #!/usr/bin/perl use overload q(<) => sub {}; my %h; for (my $i=0; $i<50000; $i++) { $h{$i} = bless [ ] => 'main'; print STDERR '.' if $i % 1000 == 0; } ----------------- end snip ------------
the above runs in about .4 sec, while on C5.2 it takes 8-12 seconds.
On Wed, Aug 27, 2008 at 6:18 AM, Mark Pryor tlviewer@yahoo.com wrote:
Can not wait for update, I have to build Perl 5.10.0 from src for my work on CentOS 5.2. I installed this into /opt/perl for now, so there is no impact on rpm Perl package.
Waiting for fixed rpm of Perl ...
On Tue, Aug 26, 2008 at 2:08 PM, Karanbir Singh mail-lists@karan.org wrote:
Actually, this is stated in the upstream bugzilla Florin referred to:
https://bugzilla.redhat.com/show_bug.cgi?id=379791#c11
see also #14.
However, according to the bugzilla, their fix is still not perfect and they are "working on it" (as of today).
Akemi
Akemi Yagi wrote:
While forking the whole perl subsection of the distro is a bit drastic, I am quite happy to have a perl in C5Plus. Does someone want to get in touch with Keith and get a summary on what needs fixing in this case ? Also - if the conversation was to take place on centos-devel list, would be much cooler.
Upstream have said the fix will be in 5U3, and considering that might be still a few months away, could we get something sorted before then ?
( questions, since I dont use perl myself )
hello All,
--- On Mon, 8/25/08, Florin Andrei florin@andrei.myip.org wrote:
ftp://download.fedora.redhat.com/pub/fedora/linux/updates/8/SRPMS/perl-5.8.8-40.fc8.src.rpm
Using the above SRPM, I've updated perl on 2 LAMP boxes, i386 and multi-lib x86_64.
The bless/overload bug is absent and perl is improved overall, especially any CPAN test code that uses the Test-Harness. I'm seeing approx. 25% speed increase in all the test suites.
In case anyone else is looking for a quick solution to the bug in 5.8.8-10, I believe this is a good approach.
The only gotcha is that the Fedora perl suite uses a separate perl-CPAN, while the RH suite includes it in core perl.
On Thu, Aug 28, 2008 at 2:28 PM, Mark Pryor tlviewer@yahoo.com wrote:
This perl discussion thread has moved to the centos-devel mailing list. Please see:
http://lists.centos.org/pipermail/centos-devel/2008-August/003144.html
and join in that thread if you wish.
Thanks,
Akemi
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Akemi Yagi -
Florin Andrei -
Karanbir Singh -
Karanbir Singh -
Mark Pryor -
Scott Silva -
Stephen John Smoogen -
Tom Lanyon -
Vnpenguin