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On 27 February 2019 03:27 Ben Burke via dovecot <
<a
href="mailto:dovecot@dovecot.org">dovecot@dovecot.org</a>>
wrote:
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Hi,
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I'm running dovecot 2.2.x and I'm having an issue where I see many
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dovecot processes use all the available IO on a server. According to
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iotop the worst offenders seem to be in this state (NOTE: I swapped in
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phony username & IP info):
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dovecot/imap [someusername 123.456.789.012 UID SEARCH]
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The server in question is running with Maildirs on top of an XFS
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filesystem. Is there anything I can do to optimize "UID SEARCH" or
find
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out why it's being a problem? I've read
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<a href="https://wiki2.dovecot.org/PerformanceTuning"
rel="noopener"
target="_blank">https://wiki2.dovecot.org/PerformanceTuning</a>
and the linked pages.
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By "being a problem" I mean iostat -xmt 1 /dev/diskdevice shows
100%
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utilization for long periods and in some cases io service times are
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taking many seconds... which causes thunderbird to timeout when doing
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things like appending messages to user "Sent" mailboxes.
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Any ideas?
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Thanks,
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Ben Burke
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Are you using FTS? If not, you should. See
https://wiki.dovecot.org/Plugins/FTS
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<pre>---
Aki Tuomi</pre>
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