> ok... we're making progress. After swapping the LSI HBA for a Dell H800 the
> issue disappeared. Now, I'd rather not use those controllers because they
> don't have a JBOD mode. We have no choice but to make individual RAID0
> volumes for each disks which means we need to reboot the server every time we
> replace a failed drive. That's not good...
Earlier you said you had eliminated the ZIL as an issue, but one difference
between the Dell H800 and the LSI HBA is that the H800 has an NV cache (if
you have the battery backup present).
A very simple test would be when things are running slow, try disabling
the ZIL temporarily, to see if that makes things go fast.
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