Comments on: Fix a bug in Ruby’s configure.in and get a ~30% performance boost.

By: Unix signal programming in Ruby « Spakman loves triangles

Unix signal programming in Ruby « Spakman loves triangles — Tue, 27 Apr 2010 11:16:38 +0000

[...] Joe Damato found, MRI 1.8 with pthreads enabled is rather rt_sigprocmask() happy. It seemed obvious that all that [...]

By: lazzarello

lazzarello — Sat, 24 Apr 2010 01:58:35 +0000

Heya. I applied your patch to ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux] in Debian stable and rebuilt the package. It does not remove the dominance of the rt_sigprocmask syscall in your test script. I ran the script for 24 seconds and it called that syscall 416614 times.

By: cryptoromantic

cryptoromantic — Thu, 25 Feb 2010 10:04:16 +0000

so what is the underlying bug here – that get/setcontext is completely unnecessary because green threads are being used even with pthreads enabled, or that some work get/setcontext is doing is necessary, but it also always calls sigprocmasks (which is unnecessary), and this calls for a better decomposition of the get/setcontext call… ?

By: Seth Thomas Rasmussen

Seth Thomas Rasmussen — Tue, 02 Feb 2010 01:22:34 +0000

Great work! I've been investigating these issues around –enable-pthread recently as I *just* became aware of their significance.. and I'm surprised, frankly.. there seem to be a lot of people that knew this, yet a lot of people who still don't and who still run into tutorials like the popular Hivelogic one which recommends you use –enable-pthread.

By: staffing1

staffing1 — Thu, 10 Dec 2009 00:30:41 +0000

Brilliant work! I hope the guys upstream patch it in.
www.staffingpower.com

By: staffing1

staffing1 — Wed, 09 Dec 2009 16:30:41 +0000

Brilliant work! I hope the guys upstream patch it in.
www.staffingpower.com

By: nigelkersten

nigelkersten — Thu, 05 Nov 2009 15:41:57 +0000

According to Matz, this isn't a problem for Ruby 1.8.7

http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ru...

yet I'm still seeing performance improvements on the ruby benchmark suite when applying your patch…

By: redditrebel

redditrebel — Thu, 08 Oct 2009 20:59:44 +0000

XBMC and Boxee(based on XBMC) suffer from this on newer 64 bit kernels, calling rt_sigprocmask a bazillion times per second and basically eating a whole CPU.

I stopped trying to debug it as the developers were truculent about even supporting newer 64 bit installs, ever.

I wouldn't be surprised if this is the cause.

By: ice799

ice799 — Wed, 13 May 2009 23:10:43 +0000

Hi.

Check out my previous blog post which explains this: http://timetobleed.com/ruby-threading-bugfix-sm...

Thanks for reading.

By: Florian Ebeling

Florian Ebeling — Wed, 13 May 2009 15:23:51 +0000

Someone should eventually figure out what this usage of pthread is there for in the first place. My best theory is that it keeps timeouts working even when you have native function calls. Ruby green / simulated threads would otherwise not be able to step in. But I could not really find a confirmation for this. Anyone having more insight on this?