Re: [Caml-list] Re: OCaml is broken

[Gerd Stolpmann <gerd@gerd-stolpmann.de>]

Am Dienstag, den 22.12.2009, 13:04 +0100 schrieb Erik Rigtorp:
> On Mon, Dec 21, 2009 at 23:50, Erik Rigtorp <erik@rigtorp.com> wrote:
> > Some IPC Benchmarks, Solaris 10 on a quad core Intel Core2 Duo. The
> > benchmarks are running on a cpuset with 1 core. I measure the time
> > from sending in one process until the other process receives the
> > message. So a context switch and the message passing is included in
> > the measurements.
> >
> > Max/Min/Avg
> > * Pipes: 28205/5973/6259
> > * Unix domain sockets: 44256/7748/8153
> > * SYSv message queues: 19197/5895/6173
> > * Posix message queues: 37399/10965/11303
> > * TCP on loopback: 29017/7471/7885
> >
> > So the latency is roughly 10µs for all these solutions. That latency
> > is pretty high and would be several times the processing time of the
> > message itself.
> 
> Some more benchmarks:
> 
> Max/Min/Avg
> * Spinlocking shm: 50897/403/761  (This one utilizes multiple cores,
> since one core is just burning while waiting for data)
> * Pthreads mutex shm: 27582/5246/6577
> 
> Forgot to say that all measurements are in nanoseconds.

That's for communication between processes, right? How would the picture
be different (especially comparing the latter two) if you do message
passing between threads? If I remember correctly, threads are more
light-weight in Solaris than processes. That could also affect context
switching times, and scheduler decisions.

Do you have source code? I could also run in on Linux, for comparison.

Gerd
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