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Date: Sat, 16 Jan 2010 00:46:09 +1100
From: Andrew Snow <andrew@modulus.org>
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To: Ivan Voras <ivoras@freebsd.org>,  freebsd-fs@freebsd.org
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Subject: Re: An old gripe: Reading via mmap stinks
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Ivan Voras wrote:
>> Hi Mikhail, I assume these tests were done on UFS.  Have you tried 
>> ZFS? I'm curious to see the results.

> I suspect it would be noticably worse :) AFAIK ZFS integration with mmap 
> does at least one extra in-memory data copy.

True but ZFS also has its own quite aggressive read-ahead algorithm

- Andrew