pveperf: very bad fsyncs/second :(

[mcflym]

Looks god now;-)

When discard is disabled on the partitions you most add this to your daily cron job to maintain speed on the disk:

/etc/cron.daily/fstrim
-----------------------------------------------------------------
#!/bin/sh


PATH=/bin:/sbin:/usr/bin:/usr/sbin


ionice -n7 fstrim -v /


ionice -n7 fstrim -v /var/lib/vz
------------------------------------------------------------------

chmod a+x /etc/cron.daily/fstrim

thank you!

it is enough to create this file with nano and set chmod?

i wish you a lot of presents for christmas eve...

 

[mir]

it is enough to create this file with nano and set chmod?

yes to both.

 

[mir]

Can't remember the Proxmox default CD install.

Proxmox defaults to ext3 with barrier=0. Proxmox defaults to ext4 with barrier=1.

@mir: do you notice any performance advantage using either discard or that script (w/o discard)? Newer SSDs, especially the Samsungs handle GC so effectively that discard's not even necessary any more.

Using discard as mount option reduces performance with a order of magnitude between 10-30. The script does not reduce the performance noticeably except while running but ionice helps alot on performance since normal work has a lower nice level.

Whether trim is useful I don't know but everybody which has a knowledge of the matter recommends running fstrim routinely. maybe this has improved in kernels >= 3.10 but since proxmox is using a 2.6.32 kernel I am pretty certain that fstrim is still needed.