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Date: Sat, 09 Jan 2010 12:32:04 +1100
From: Andrew Snow <andrew@modulus.org>
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Subject: Re: ZFS performance degradation over time
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Ivan Voras wrote:
> It is true that ZFS in theory doesn't do very well with random writes of 
> any kind - the kind that torrent clients do should actually be the worst 
> case for ZFS, *but*, this very much depends on the actual workload.


ZFS has aggressive read-ahead for sequential read-aheads, so its worth 
noting that the performance problem can be mitigated by having lots of 
RAM free for read-ahead, as well as multiple vdevs in the zpool (so that 
it can be seeking all disks at once)


- Andrew