Vermaden, something extra we forgot to mention on ZFS and disk alignment: I've seen a noticeable improvement when the ZIL on the SSD is properly aligned, in that case i've used Gnop to 4K-align a mounted memory drive then instructed ZFS to mirror log on the SSD with the properly aligned memory drive, I then deleted the MD and the Gnop device yet ZFS keeps a 12 ashift on the log disk and it's what we want. [strike]I'll add the instructions later.[/strike]
ZIL / Log Device /dev/ada5
for proper alignement calculate dd seek with this formula: device media size / 1024000 -1
Code:
# diskinfo -v ada5 #### media size: 128035676160
# echo "128035676160 / 1024000 - 1" | bc #### seek: 125033
# dd if=/dev/zero of=tmpdsk0 bs=1024000 count=1 seek=125033
# mdconfig -a -t vnode -f tmpdsk0
# gnop create -S 4096 md0
# gpart create -s gpt ada5
# gpart add -t freebsd-zfs -l zlog -b 2048 -a 4k ada5
# zpool add znas log mirror md0.nop gpt/zlog
# zpool detach znas md0.nop
# gnop destroy md0.nop
# mdconfig -d -u md0
# zdb znas | grep ashift
to remove ZIL use
Code:
# zpool remove znas zlog
ps. I'm posting here because this thread is probably one of the most complete ZFS installation instructions found online and it's good to keep it alive.