[ceph-users] Re: Wide EC pool causes very slow backfill?

Hi,

Given that the first host added had 19 OSDs, with none of them anywhere near the target capacity, and the one we just added has 22 empty OSDs, having just 22 PGs backfilling and 1 recovering seems somewhat underwhelming.

Is this to be expected with such a pool? Mclock profile is high_recovery_ops.

Since you are already using the high_recovery_ops profile, you could additionally try incrementing "osd_max_backfills" (default: 1) by a small amount (2 or 3) using the following procedure and see if it improves the backfill rate: https://docs.ceph.com/en/quincy/rados/configuration/mclock-config-ref/#steps... -Sridhar