Hello,
I'm adding OSDs to a 5 node cluster using Quincy 17.2.5. The network is
a bonded 2x10G link. The issue I'm having is that the rebalance
operation seems to impact client I/O and running VMs do not . OSDs are
big 6'4TB NVMe drives, so there will be a lot of data to move.
With previous versions it was easy to throttle down the rebalance with
"ceph config set osd osd_max_backfills", but as Quincy uses MClock,
those values are not used. In fact, default values are overridden with 1000.
If I'm understanding the MClock behavior it will use the estimated
osd_mclock_max_capacity_iops_ssd (benchmarked at OSD deploy time) and
allow client/rebalance/backfill/trims/scrubs I/O to fill the drive with
IOPs up to what is defined in osd_mclock_profile (default value is
high_client_ops). Am I correct?
How could I throttle down the rebalance so it gives more headroom for
client I/O?
Many thanks in advance.
--
_______________________________________________
ceph-users mailing list -- ceph-users@ceph.io
To unsubscribe send an email to ceph-users-le...@ceph.io
