Re: [Patch][RFC] Disabling per-tgid stats on task exit in taskstats

From: Nick Piggin
Date: Thu Jun 29 2006 - 14:04:30 EST


Paul Jackson wrote:
You're probably correct on that model. However, it all depends on the actual
workload. Are people who actually have large-CPU (>256) systems actually
running fork()-heavy things like webservers on them, or are they running things
like database servers and computations, which tend to have persistent
processes?


It may well be mostly as you say - the large-CPU systems not running
the fork() heavy jobs.

Sooner or later, someone will want to run a fork()-heavy job on a
large-CPU system. On a 1024 CPU system, it would apparently take
just 14 exits/sec/CPU to hit this bottleneck, if Jay's number of
14000 applied.

Half the CPUs in that system are probably going to be several
router hops away, won't they? I'll take a guess and say they're
an order of magnitude too optimistic for such a system ;)

--
SUSE Labs, Novell Inc.
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