Guest os have iops lower than Host OS


New Member
Dec 6, 2018
Hi all,
im pretty new on proxmox VE, and finding a sotrage solution for performance and stabiility.
I surprised about IOPS of VMs on proxmox always lower than IOPS of NVME SSD specification.

Hardware as bellow:
- 2 sata SSD installed Promox VE 5.2 and set raid 1 for them using hard raid
- 6 NVME SSD grouped an raid 10 array using software raid of ZFS.

And results as bellow:
- the result on CENTOS-VM of read and write random for ZFS array raid 10

- Another result on HOST of Read and write random for single disk non raid:

i also test with many file system (xfs, ext4, zfs ) and raid level ( raid 0, raid1, raid10) but IOPS of Guest always lower and lower than HOST.
kindly advise me this case.


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