ZFS & MySQL

[Alexander Leidinger]

Quoting Peter Schuller <peter.schuller at infidyne.com> (from Fri, 16 Nov  
2007 01:36:47 +0100):

>> Can somebody who has done MySQL benchmarks (e.g. Kris Kennaway, but I
>> don't want to point fingers :) ) try them when MySQL is hosted on ZFS?
>> I'm currently having a problem where mysqld gets stuck in "zfs" state
>> and it becomes completely unusable and unkillable. The machine generally
>> works, but cannot be rebooted from the OS in this case (it must be
>> manually power-cycled).
>
> I had an unkillable MySQLd a while ago that required reboot (pre-RELENG_7
> CURRENT). It was in uninterruptable sleep, but I can't swear to whether it
> was in zfs state. This was on a quadcore core 2 duo.
>
> I can do some sysbenching on a dual core machine with and without ZFS, but it
> sounds like that won't be more useful than what you already have available.

If you really do benchmarks and not failure verification, you should  
take care about the recordsize attribute in the corresponding ZFS,  
else you may get suboptimal performance (this is a suggestion of SUN  
for the use of ZFS with DBs, personally I don't have access to a  
machine where the DB is used enough that we could notice a performance  
difference).

Bye,
Alexander.

-- 
The most disagreeable thing that your worst enemy says to your face does
not approach what your best friends say behind your back.
		-- Alfred De Musset

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