Reoccuring ZFS performance problems

[Adrian Gschwend]

On 10.03.14 18:31, Steven Hartland wrote:



> Looks like you may be out of IOP/s but just incase, are you using TRIM
> at all?
> sysctl -a |grep trim

vfs.zfs.vdev.trim_on_init: 1
vfs.zfs.vdev.trim_max_pending: 64
vfs.zfs.vdev.trim_max_bytes: 2147483648
vfs.zfs.trim.enabled: 1
vfs.zfs.trim.max_interval: 1
vfs.zfs.trim.timeout: 30
vfs.zfs.trim.txg_delay: 32
kstat.zfs.misc.zio_trim.bytes: 0
kstat.zfs.misc.zio_trim.success: 0
kstat.zfs.misc.zio_trim.unsupported: 115
kstat.zfs.misc.zio_trim.failed: 0

so looks like trim is enabled

> If you are what does "gstat -d" show?

It looks like finally my MySQL process finished and now the system is
back to completely fine:

dT: 1.010s  w: 1.000s
 L(q)  ops/s    r/s   kBps   ms/r    w/s   kBps   ms/w    d/s   kBps
ms/d   %busy Name
   10    203      0      0    0.0    192   1674   38.8      0      0
0.0   95.2| vtbd0
    0      0      0      0    0.0      0      0    0.0      0      0
0.0    0.0| vtbd0p1
    0      0      0      0    0.0      0      0    0.0      0      0
0.0    0.0| vtbd0p2
   10    203      0      0    0.0    192   1674   39.0      0      0
0.0   95.5| vtbd0p3
    0      0      0      0    0.0      0      0    0.0      0      0
0.0    0.0| cd0
    0      0      0      0    0.0      0      0    0.0      0      0
0.0    0.0| gptid/e402ecce-89ca-11e2-a867-3264262b9894
    0      0      0      0    0.0      0      0    0.0      0      0
0.0    0.0| gptid/e4112d88-89ca-11e2-a867-3264262b9894

I restarted MySQL now, curious how long it will take.

> You also mention your using mysql, have you applied the standard tuning
> for mysql on ZFS?

At first I didn't so anything special with MySQL, during the process I
redid the MySQL ZFS with a new record size:

# zfs get recordsize tank/storage/data/db/data
NAME                       PROPERTY    VALUE    SOURCE
tank/storage/data/db/data  recordsize  16K      local

regards

Adrian