Messages in this thread | | | Date | Sat, 24 Feb 2007 06:15:56 +0100 | From | Nick Piggin <> | Subject | Re: [rfc][patch] dynamic resizing dentry hash using RCU |
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On Sat, Feb 24, 2007 at 01:07:23PM +0900, KAMEZAWA Hiroyuki wrote: > On Fri, 23 Feb 2007 16:37:43 +0100 > Nick Piggin <npiggin@suse.de> wrote: > > > +static void dcache_hash_resize(unsigned int new_shift); > > +static void mod_nr_dentry(int mod) > > +{ > > + unsigned long dentry_size; > > + > > + dentry_stat.nr_dentry += mod; > > + > > + dentry_size = 1 << dentry_hash->shift; > > + if (unlikely(dentry_stat.nr_dentry > dentry_size+(dentry_size>>1))) > > + dcache_hash_resize(dentry_hash->shift+1); > > + else if (unlikely(dentry_stat.nr_dentry < (dentry_size>>1))) > > + dcache_hash_resize(dentry_hash->shift-1); > > +} > > + > > Do we need to do this kind of resizing in implicit automatic way ? > I think it's good to show contention rate by /proc and add sysctl for > resize this.
Well having the kernel automatically adjust to the workload is better than a sysctl. But it could well be the case that these simple heuristics are bad (though they're fine for my system).
But a manual override is a good idea as well. - 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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