IO Delay 50% or higher on fresh install


May 12, 2014
Portland, Oregon, United States
Fresh install on fresh 1TB RAID 10 array

this image was from restoring a VM from the local HDD (i only have local drives)


that was a < 50GB LZO backup and everything slowed down a LOT, this is a fresh install that i just installed today.. made sure to update everything so its all freshly up to date. (2/13/17)

anyone have any idea why a RAID 10 would have IO delay this high when i was on a single 1TB HDD no raid and it was not even this bad..


Version: 4.4-1/eb2d6f1e


Active Member
Feb 3, 2012
Are you coming from an older Proxmox like v3? If so this is likely the changes to barriers being enabled by default and no way currently to disable this on Thin LVM. There's a feature request to have it as an option which I hope will get implemented sooner or later for lxc.rootfs.options like this to be added, same with stuff like noatime options.


Well-Known Member
Mar 3, 2013
my test location
Is the IO-Delay only present during the restore ?
Your screenshot suggests that to me.

If so, there seems to be an issue, because according to your screenshot the io delay was roughly 50 minutes, the backup was 50GB. That suggests a restore rate of 17 MB/s. Unless you're using really old drives, that is too low. Higher than usual IO-Delay should still be expected tho. (i don't run proxmox without SSD's anymore)


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