Messages in this thread | | | Date | Fri, 23 Jul 2004 13:27:24 +1000 | From | Nick Piggin <> | Subject | Re: [RFC] Patch for isolated scheduler domains |
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Ingo Molnar wrote: > * Dimitri Sivanich <sivanich@sgi.com> wrote: > > >>I'm interested in implementing something I'll call isolated sched >>domains for single cpus (to minimize the latencies involved when doing >>things like load balancing on certain select cpus) on IA64. >> >>Below I've included an initial patch to illustrate what I'd like to >>do. I know there's been mention of 'platform specific work' in the >>area of sched domains. This patch only addresses IA64, but could be >>made generic as well. The code is derived directly from the current >>default arch_init_sched_domains code. > > > it looks good to me - and i'd suggest to put it into sched.c. Every > architecture benefits from the ability to define isolated CPUs. >
Cool. Have you actually tried running it? With Ingo's correction, it should work fine but I don't think anyone has tested this.
> One minor nit wrt. this line: > > + cpu_sd->flags &= ~(SD_BALANCE_NEWIDLE | SD_BALANCE_EXEC | > + SD_BALANCE_CLONE); /* Probably redundant */ > > i'd suggest to set it to 0. You dont want WAKE_AFFINE nor WAKE_BALANCE > to move your tasks out of the isolated domain. > > >>- Assuming boot time configuration is appropriate ('isolcpus=' in my example), >> is allowing boot time configuration of only completely isolated cpus >> focusing too narrowly on this one concept, or should a boot time >> configuration allow for a broader array of configurations, or would other >> types of sched domain configurations be addressed separately? > > > i'd prefer to go with this simple solution and wait for actual usage > patterns to materialize. If it becomes popular we can define a syscall > to configure the domain hierarchy (maybe even the parameters) runtime. >
Seconded. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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