ZFS and large directories - caveat report

[Luiz Otavio O Souza]

On Jul 21, 2011, at 5:04 PM, Ivan Voras wrote:

> The "load.." lines in between are  me hitting Ctrl-T for process info.
> Observe almost 20 seconds delay in the middle of "ls"!

What do you have for the the first column on gstat (L(q) values) ?

The server in question is a DELL R710 that comes as a poor choice on bought (nobody notice the SATA disks until the server was installed - then it was too late for a exchange).

It was a lot worse at beginning and adding the following lines (to /boot/loader.conf) did help a little bit (it is usable now, even when it is fully loaded by find requests - usable but not normal -).

vfs.zfs.vdev.min_pending=1
vfs.zfs.vdev.max_pending=1

Not sure if this will help with your hardware, but you can give it a try if you're seeing high values for the L(q) column.

Luiz