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From: "Robert N. M. Watson" <rwatson@freebsd.org>
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To: Andriy Gapon <avg@freebsd.org>
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Cc: Andre Oppermann <andre@freebsd.org>, Jeff Roberson <jeff@freebsd.org>,
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Subject: Re: zfs + uma
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On 19 Sep 2010, at 09:42, Andriy Gapon wrote:

> on 19/09/2010 11:27 Jeff Roberson said the following:
>> I don't like this because even with very large buffers you can still =
have high
>> enough turnover to require per-cpu caching.  Kip specifically added =
UMA support
>> to address this issue in zfs.  If you have allocations which don't =
require
>> per-cpu caching and are very large why even use UMA?
>=20
> Good point.
> Right now I am running with 4 items/bucket limit for items larger than =
32KB.

If allocate turnover is low, I'd think that malloc(9) would do better =
here. How many allocs/frees per second are there in peak operation?

Robert=