Update on recent SMP contention work

Pierre Abbat phma at bezitopo.org
Thu Oct 17 23:31:47 PDT 2013


On Wednesday, October 16, 2013 23:34:44 Matthew Dillon wrote:
>     The jist of this work is that there is no longer virtually any
>     contention for most process-related activities, including heavy use
>     of fork and fork/exec in 'make', '/bin/sh', and other utilities.
>     Anything which forks and/or execs a lot (scripts, bulk builds, service
>     daemons, etc) will now run as close to optimally as it is possible to
>     run on a multi-core box.
> 
>     In particular with the last change to the namecache code, our bulk
>     ports builds look pretty insane on monster (our 48-core opteron box).
>     Now during a bulk dports build, the load can pop up to 300 with
> concurrent compiles and of that 300 there will be 295 non-contending "R"un
> state processes and only 5 contending "D" state processes.  And it all
> happens with virtually *NO* IPI traffic between cpus.

Sounds great! Where can I get a 48-core Opteron?

Pierre
-- 
When a barnacle settles down, its brain disintegrates.
Já não percebe nada, já não percebe nada.





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