====== Rebalance / recovery speed ======

Form [[https://www.suse.com/support/kb/doc/?id=000019693|]]:
  * **osd max backfills** This is the maximum number of backfill operations allowed to/from OSD. The higher the number, the quicker the recovery, which might impact overall cluster performance until recovery finishes. 
  * **osd recovery max active** This is the maximum number of active recover requests. Higher the number, quicker the recovery, which might impact the overall cluster performance until recovery finishes. 
  * **osd recovery op priority** This is the priority set for recovery operation. Lower the number, higher the recovery priority. Higher recovery priority might cause performance degradation until recovery completes. 
    

Defaults in Proxmox:
<code bash>
# ceph config get osd osd_max_backfills
1
# ceph config get osd osd_recovery_max_active 
0
# ceph config get osd osd_recovery_op_priority
3
</code>

Speed up CEPH recovery:
<code bash>ceph tell 'osd.*' injectargs --osd-max-backfills=2 --osd-recovery-max-active=6 --osd_recovery_op_priority=2</code>   
  or 
<code bash>ceph tell 'osd.*' injectargs --osd-max-backfills=3 --osd-recovery-max-active=9 --osd_recovery_op_priority=2</code>

And return to defaults:

<code bash>ceph tell 'osd.*' injectargs --osd-max-backfills=1 --osd-recovery-max-active=0 --osd_recovery_op_priority=3</code>