Ruby is much slower on linux when compiled with --enable-pth

Ruby
21

On 9/26/07, M. Edward (Ed) Borasky [email protected] wrote:

If you have Ruby (1.8), Tcl and Tk all together on the same Linux
system, they must all be compiled with the same setting for “pthreads”

Which is why every precompiled binary package of Ruby that I’ve seen
is linked with pthread.

22

On Sep 26, 2007, at 10:00 , Rick DeNatale wrote:

On 9/25/07, Eric H. [email protected] wrote:

On Sep 25, 2007, at 14:59 , Roger P. wrote:

Does ruby compile by default with pthreads enabled?

No.

I seem to recall that one of the library extensions (Tk if I’m not
mistaken) either wouldn’t compile or complained loudly if if found
that Ruby had been compiled without pthreads enabled.

Correct.

If you check out from source and run:

autoconf && ./configure && make

ruby will not be linked with the system pthread library.

23

Alexey V. schrieb:

25 % difference.
on Mac OS 10.5, I get even 2x the performance without pthread. it’s
evil!

[murphy]

24

How can one check if theirs is compiled with pthreads or not?
Alexey V. wrote:

On 9/26/07, M. Edward (Ed) Borasky [email protected] wrote:

If you have Ruby (1.8), Tcl and Tk all together on the same Linux
system, they must all be compiled with the same setting for “pthreads”

Which is why every precompiled binary package of Ruby that I’ve seen
is linked with pthread.

25

On Tue, Sep 4, 2007 at 5:53 AM, Adam K. [email protected] wrote:

Hi,

I was seeing significant performance differences between ruby 1.8.4 on
an old distribution and a newer one. I spent some hours tracking down
the differences and it appears that --enable-pthread causes ruby to be
significantly slower.
[snip]
Has anyone else witnessed this? Is this a “feature” that’s to be expected?

Yes, we’ve hit this - in Centos 5, the default ruby build is 1.8.5 (!)
with --enable-pthread. What I’d like to know is why[1]? Is it just
hand-waving conservatism (just-in-case-we-need-it), RedHat policy to
enable pthreads everywhere or is there a specific reason why pthreads
have to be enabled, e.g. there’s an Oracle driver that requires it or
some such?

Anyone have any ideas?

Regards,
Sean

[1] Apart from why anyone thinks putting an unstable version of ruby
in their distro is a good idea

26

How can one check if theirs is compiled with pthreads or not?

Maybe try with “ldd” on the ruby binaries

27

tk, by default, compiles with pthread
ruby ships with exteensive bindings to tk and so has to be kept
compatible to use ruby and tk together.
that’s the only reason i can think of.

^ manveru