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Date: Sun, 24 Feb 2008 09:24:44 -0500
From: Brian Biskeborn <bbiskebo@Princeton.EDU>
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To: Peter Schuller <peter.schuller@infidyne.com>
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Cc: freebsd-current@freebsd.org, Richard Todd <rmtodd@ichotolot.servalan.com>
Subject: Re: ZFS: data sometimes not getting correctly flushed to
 disk	(possible mmap/write issue)?
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This has been happening to me for a week or so (same setup - Dovecot on 
ZFS). I'll disable mmap and see whether it persists.

Brian

Peter Schuller wrote:
>> 3) ktracing gen2.py shows that the py-mutagen library seems to do both
>> write()s and read/write mmap()s to the file to update the file.
> 
> FWIW, ever since a dovecot installation of mine was moved onto ZFS one gets 
> sporadic 'internel errors' from dovecot. Dovecot logs that index files are 
> corrupt, and marked broken. Recovery involves re-selecting the IMAP mailbox.
> 
> In response to your post, I recently turned OFF use of mmap in dovecot 
> (mmap_disable = yes), and the problem seems to have gone away immediately.
> 
> If it should show up again in spite of mmap being disabled I will post a 
> follow-up, but it's been long enough that I believe the problem to be gone.
>