zfs + uma
avg at freebsd.org
Tue Sep 21 06:20:05 UTC 2010
on 19/09/2010 11:42 Andriy Gapon said the following:
> 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?
> Good point.
> Right now I am running with 4 items/bucket limit for items larger than 32KB.
But I also have two counter-points actually :)
1. Uniformity. E.g. you can handle all ZFS I/O buffers via the same mechanism
regardless of buffer size.
2. (Open)Solaris does that for a while and it seems to suit them well. Not
saying that they are perfect, or the best, or an example to follow, but still
that means quite a bit (for me).
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