Recent (probably MacOS) mail app provoking endless cyrus.index writes on 2.3 server.

[Eric Luyten]

On Tue, October 13, 2015 10:43 pm, Bron Gondwana wrote:
> On Wed, Oct 14, 2015, at 00:26, ktm at rice.edu wrote:
>
>> The El Capitan Mac Mail was recently released. It definitely has a problem.
>>  We saw our typical sync log size go from 10k when busy to 100k+. We are
>> going to recommend that people wait to upgrade to that release until the
>> problem is addressed.
>
> I'll look into whether this is a problem (or as much of a problem) on later
> releases! Just to be clear - have you tracked the issue down to the EXPUNGE
> command using IO?
>
>
> (It's unlikely that 2.3 will be patched to make EXPUNGE more efficient unless
> someone else wants to do it.  I've already spent a year fixing that code, and
> it's called 2.4)


Bron,


I turned off imapd/popd process re-use last night and while this
has upped the server load a few dozen percent (measured as load
average, plenty of CPU cycles remaining) it appears to have dampened
the I/O impact somewhat and it will allow me to more easily capture
the start of the client-server conversations leading to the loop.

If Rice is experiencing a similar phenomenon, more Cyrus versions
and installations may be impacted as we speak.


Eric Luyten, Computing Centre VUB/ULB.