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I know building a single 50 drives RaidZ2 is a bad idea. As I said,
it's a legacy that I can't easily change. I already have a backup
pool with 7x10 drives RaidZ2 to which I hope I will be able to
switch this week. I hope to get some better results and less
crashing...<br>
<br>
What is interesting is that when the 'event' happens, server works
normaly, ZFS is accessable and writable(at least, there is no errors
in log files), only iscsi reports errors and drops the connection.
Another interesting thing is that after the 'event', all write
stops, only read continues for another 30min. After 30min all
traffic stops for half an hour. After that, everything starts to
coming back up... Weird?!<br>
<br>
Matej<br>
<br>
<div class="moz-cite-prefix">On 09. 05. 2015 02:49, Richard Elling
wrote:<br>
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<div class="">On May 5, 2015, at 9:48 AM, Matej Zerovnik <<a
moz-do-not-send="true" href="mailto:matej@zunaj.si"
class="">matej@zunaj.si</a>> wrote:</div>
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<div style="font-family: Calibri,sans-serif; font-size:
11pt;" class="">I will replace the hardwarw in about 4
months with all SAS drives, but I would love to have a
working setup for the time being as well;)<br class="">
<br class="">
I looked at smart stats and there doesnt seem to be
any errors. Also, no hard/soft/transfer error reported
by any drive. Will take a look at service time
tomorrow, maybe put the drives to graphite and look at
them over a longer period.<br class="">
<br class="">
I looked at iostat -x status today and stats for pool
itself reported 100% busy most of the time, 98-100%
wait, 500-1300 transactions in queue, around 500
active,... First line, that is average from boot, says
avg service <a moz-do-not-send="true"
href="http://time.is" class="">time.is</a> around
1600ms which seems like aaaalot. Can it be due to
really big queue?<br class="">
<br class="">
Would it help to create 5 10drives raidz pools instead
of one with 50 drives?<br class="">
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<div>It is a bad idea to build a single raidz set with 50
drives. Very bad. Hence the zpool</div>
<div>man page says, "The recommended number is between 3 and 9
to help increase performance."</div>
<div>But this recommendation applies to reliability, too.</div>
<div> -- richard</div>
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