Ok, yes this is normal. The system have not enough power. 2 Disk and backup on same machine, that can't go fine.
BUFFERED READS: 31.33 MB/sec
AVERAGE SEEK TIME: 15.26 ms
FSYNCS/SECOND: 26.44
31,33 MB/s is not really much. And fsync should me much more higher. A good value is about 3000 upward. For example here two servers.
Littel HP with 4 SATA Disks in Raid10
Code:
CPU BOGOMIPS: 24742.04
REGEX/SECOND: 1524866
HD SIZE: 9.72 GB (/dev/dm-0)
BUFFERED READS: 188.50 MB/sec
AVERAGE SEEK TIME: 7.78 ms
FSYNCS/SECOND: 5259.39
DNS EXT: 44.98 ms
Or an Supermicro with 6 SATA Disk in ZFS Raid10
Code:
CPU BOGOMIPS: 40002.00
REGEX/SECOND: 2686294
HD SIZE: 1920.82 GB (v-machines)
FSYNCS/SECOND: 6812.31
DNS EXT: 61.02 ms
The Systems Performance is not always depending on these values, but you read that you can have problem with your hardware. Or
not enough / to little harddrives.
And the last thing: Softraid with mdadm is not supportet... but yes should also work
with more disks, or some Enterprise SSD's.
I recommend, that you upgrade to newest PVEversion too In the course of the hardware change / upgrade.
Please Post the details of your HDD's
Code:
smartctl -a /dev/sda
smartctl -a /dev/sdb
smartctl -a /dev/sdc