pw operations slow under zfs load

Terje Elde terje at
Tue Aug 4 21:18:09 UTC 2015

On 4. aug. 2015, at 23:07, javocado <javocado at> wrote:

> So, what's going on here? How does a busy pool with it's own set of drives
> (which operate off an HBA) affect the speed of operations involving the
> boot volume (a UFS-formatted SSD connected to the mobo)?

First thing that springs to mind is that it's not just a matter of simple IO. There's also locking (see man-page for flock and/or lockf). Could this be as simple as whatever is causing the work-load on your ZFS-volume holding a shared lock, on something pw wants to grab an exclusive lock on, prior to doing the actual change?


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