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Date: Fri, 27 Dec 2013 15:29:04 -0800
From: Alfred Perlstein <alfred@freebsd.org>
Organization: FreeBSD
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To: freebsd-arch@freebsd.org
Subject: Re: Default knote hash table size is too .. small
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On 12/27/13, 2:41 PM, Adrian Chadd wrote:
> Hi,
>
> The default knote hash table size (KN_HASHSIZE) is 64. When doing
> dirty things with lots of sockets (say, 64k and more) that involve
> plenty of knote insert/remove (ie, oneshot events - think posix AIO
> and my upcoming kqueue sendfile notification stuff) it consumes stupid
> amounts of CPU.
>
> I'd like to make this a tunable so people like Adrian at Netflix can
> bump this to higher values (say 32k) but people like Adrian at
> Embedded can bump this to lower values (say 64.)
>
> Comments? I'll make the change soon if no-one objects.
>
> Thanks,

Cool!  What about auto-tune to maxfiles?

-Alfred