[pypy-dev] STM status

[Armin Rigo]

Hi Chris,

On Sat, Feb 18, 2012 at 03:51, Chris Dashiell <cdash004 at odu.edu> wrote:
> I just wanted to let you know the numbers I got on a 32 core server.
>
> 1 thread: 3280 ms
> 4 threads: 2665 ms
> 8 threads: 2976 ms
> 16 threads: 2878 ms
> 32 threads: 2714 ms

We just checked on a 24-core server (2 physical processors of 6x2
cores each).  We also get strange results, notably: the 1-thread
performance is often *better* than the 2-threads performance.  We
tried to use "taskset" to constrain which cores run the two threads,
trying notably to keep them on the same physical processor in order to
minimize inter-processor traffic, but the resulting performance
numbers make no sense at all.  For example with "taskset -c 0,2,3" it
is much faster than with any 2-numbers-only combination of 0, 2 and 3,
which makes no sense because it's only running 2 threads...


Armin