On 19-Mar-2018 14:21, Alex Chekholko wrote:
Normally I would suggest to do a diagnostic read dd from each disk, but
you
may not be able to do that with your RAID controller since it hides the
individual disks.
I run full smartctl scans on the disks once a week. In fact those were
running at the time (on both machines). Nothing turns up other than
what was posted.
My next recommendation would be a full AC cycle; can you power the host
off
for a few minutes? It's a bit cargo cult-y but sometimes it works. It
may
also help (or not) for you to spin around 3 times while the machine is
off.
Did a reboot, but not a full AC cycle. There is a battery backup on the
RAID controller, so power down is not really ever power off for that
board. When it came back up the IO rate was unchanged. Perhaps a few
minutes with the power off might clear some stuck bits elsewhere in the
system.
Checked the speed on a third similar machine, H370P controller and again
SAS
disks. This one is all SEAGATE ST4000NM0005. It was as fast as the 'A'
machine (more or less.)
Thanks,
David Mathog
mat...@caltech.edu
Manager, Sequence Analysis Facility, Biology Division, Caltech
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