AIX M:N threads? was Re: [proposal] apr_thread_setconcurrency()

[Justin Erenkrantz <je...@ebuilt.com>]

On Sun, Sep 16, 2001 at 07:11:41PM -0700, Aaron Bannert wrote:
> The only platforms that I know about that have a two-level thread model
> are AIX and Solaris. The single-level thread libs ignore setconcurrency
> because every thread is what solaris calls a "bound thread", or a kernel
> scheduled entity (it gets it's own process slot). The only exceptions
> to this rule are fully userspace thread libs, where setconcurrency is
> inherently maximized at 1.

Oh, crap, you're right.  AIX has M:N threads by default in 4.3.1+.
(Isn't it funny that IBM is adopting something that Sun is ditching?)

Okay, so, what does setconcurrency do on AIX?  How does testlockperf
work on MP AIX boxes?  I bet it'd do the same bad things as Solaris
does.  But, I know nothing about AIX.  -- justin

Re: AIX M:N threads? was Re: [proposal] apr_thread_setconcurrency()

["Victor J. Orlikowski" <vj...@dulug.duke.edu>]

On Sunday, 16 Sep 2001, at 20:05:00,
Aaron Bannert wrote:
> I wouldn't be surprised if it did the same thing as Solaris on
> testlockperf. It remains to be seen, however, how the libs perform
> on Solaris/AIX under real-world scenarios (worker MPM) w/ and w/o
> setconcurrency, and on Uni and Multiprocessor machines.

Easy enough to test (w/out playing too much in the code) on AIX.
Check the AIXTHREAD_MNRATIO environment variable.

Victor
-- 
Victor J. Orlikowski   | The Wall is Down, But the Threat Remains!
==================================================================
orlikowski@apache.org  | vjo@dulug.duke.edu | vjo@us.ibm.com

Re: AIX M:N threads? was Re: [proposal] apr_thread_setconcurrency()

[Aaron Bannert <aa...@clove.org>]

On Sun, Sep 16, 2001 at 07:44:58PM -0700, Justin Erenkrantz wrote:
> On Sun, Sep 16, 2001 at 07:11:41PM -0700, Aaron Bannert wrote:
> > The only platforms that I know about that have a two-level thread model
> > are AIX and Solaris. The single-level thread libs ignore setconcurrency
> > because every thread is what solaris calls a "bound thread", or a kernel
> > scheduled entity (it gets it's own process slot). The only exceptions
> > to this rule are fully userspace thread libs, where setconcurrency is
> > inherently maximized at 1.
> 
> Oh, crap, you're right.  AIX has M:N threads by default in 4.3.1+.
> (Isn't it funny that IBM is adopting something that Sun is ditching?)
> 
> Okay, so, what does setconcurrency do on AIX?  How does testlockperf
> work on MP AIX boxes?  I bet it'd do the same bad things as Solaris
> does.  But, I know nothing about AIX.  -- justin

I wouldn't be surprised if it did the same thing as Solaris on
testlockperf. It remains to be seen, however, how the libs perform
on Solaris/AIX under real-world scenarios (worker MPM) w/ and w/o
setconcurrency, and on Uni and Multiprocessor machines.

Whew that's a lot of variables...

Someone want to send me an AIX SMP box? ;)

-aaron