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From: "Pavlo" <devgs@ukr.net>
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Subject: ZFS and mem management
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>On 15/02/2012 13:39, Pavlo wrote:
>>

>> >> >> Unfortunately we can't afford disabling prefetch. It is too much of an>> overhead.>> >> Also I made some tests. I have process that maps file using mmap() and>> writes or reads first byte of each page of mapped file with some data.>
>Note that ZFS is designed so that it interacts somewhat badly with
>mmap() and other kernel services which rely on coherency between VM and
>IO such as sendfile(). At the very best, you will have two in-kernel
>copies of all data buffers used with such interfaces, but there have
>been sporadic reports that there are other bugs with it.
>
>If you have a test server, I'd recommend you do the same test on UFS for
>comparison.

Was going to try this... Thanks for reply.