ext4, fstab, io wait

as long as you do not have a real reason for changes, use defaults.

if you change defaults, you need to sure that the settings are suitable for your hardware and needs.
 
CPU BOGOMIPS: 38398.64
REGEX/SECOND: 2087224
HD SIZE: 19.10 GB (/dev/md2)
BUFFERED READS: 90.90 MB/sec
AVERAGE SEEK TIME: 13.46 ms
FSYNCS/SECOND: 16.16
DNS EXT: 21.89 ms
DNS INT: 7.68 ms
 
Wow ... that is terribly slow.

I see you're using software raid, that could be one of the problems. Please check the io response times on each disk individually.

Besides: You're running Proxmox VE in an unsupported environment if you use software raid.
 
Try to mount the file system with "nobarrier" option, a bit more risky (search about the implications) but definetely your fsync numbers will increase a lot
 
i have this
Code:
/dev/pve/data   /var/lib/vz     ext4    defaults,nobarrier      1       2
it's ok? or i must use only
Code:
/dev/pve/data   /var/lib/vz     ext4    nobarrier      1       2
 
i have this
Code:
/dev/pve/data   /var/lib/vz     ext4    defaults,nobarrier      1       2
it's ok?
Seems so, I've also noatime, i.e. my config is usually like that
Code:
/dev/pve/data /var/lib/vz ext4 defaults,noatime,nobarrier 0 1
of course after changes in fstab you have to remount or better reboot :)