[SOLVED] high IO z_null_int


Renowned Member
Aug 13, 2017
I was wondering if someone else has had the same issue, i checked with the iotop i see high 99% IO with znull int currently have proxmox version
5.1-41, i was wondering if the issue is with that version or recommended to update to 5.4?

pve-manager/5.1-41/0b958203 (running kernel: 4.13.13-2-pve)

root@prometheus:~# zpool status -v
  pool: rpool
 state: ONLINE
  scan: scrub repaired 0B in 1h38m with 0 errors on Fri Aug 30 20:48:35 2019

    rpool       ONLINE       0     0     0
      mirror-0  ONLINE       0     0     0
        sda2    ONLINE       0     0     0
        sdb2    ONLINE       0     0     0

errors: No known data errors

  pool: vmdata
 state: ONLINE
  scan: scrub repaired 0B in 24h22m with 0 errors on Sat Aug 31 19:32:20 2019

    NAME                                  STATE     READ WRITE CKSUM
    vmdata                                ONLINE       0     0     0
      mirror-0                            ONLINE       0     0     0
        ata-TOSHIBA_DT01ACA100_741L4SUFS  ONLINE       0     0     0
        ata-TOSHIBA_DT01ACA100_X7AMPVMNS  ONLINE       0     0     0

Thank you
Yes, this is a known issue with old versions. Your issue specifically should be fixed in kernel 4.13.16-2-pve, but upgrading to 5.4 (and then 6.0, if you want to) is your best bet in general.
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So wanted to post back and whats odd no one is working on the server and i see high ZVOL constant IO delay 20-30% any ideas?

Than you
It's okay to open a new thread for new questions instead of bumping solved ones.

For your issue: Your zpool might be scrubbing or resilvering. That can cause IO load as well. You can check using the command from your first post (zpool status -v).
Thanks for the reply, your right should of created another thread, but its not re-silvering or scrubbing what im going to do is to backup it first and format it and put 6.0 to see what happens thank you again


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