On 4/10/19 9:25 AM, jesper@xxxxxxxx wrote: >> On 4/10/19 9:07 AM, Charles Alva wrote: >>> Hi Ceph Users, >>> >>> Is there a way around to minimize rocksdb compacting event so that it >>> won't use all the spinning disk IO utilization and avoid it being marked >>> as down due to fail to send heartbeat to others? >>> >>> Right now we have frequent high IO disk utilization for every 20-25 >>> minutes where the rocksdb reaches level 4 with 67GB data to compact. >>> >> >> How big is the disk? RocksDB will need to compact at some point and it >> seems that the HDD can't keep up. >> >> I've seen this with many customers and in those cases we offloaded the >> WAL+DB to an SSD. > > Guess the SSD need to be pretty durable to handle that? > Always use DC-grade SSDs, but you don't need to buy the most expensive ones you can find. ~1.5DWPD is sufficient. > Is there a "migration path" to offload this or is it needed to destroy > and re-create the OSD? > In Nautilus release (and maybe Mimic) there is a tool to migrate the DB to a different device without the need to re-create the OSD. This is bluestore-dev-tool I think. Wido > Thanks. > > Jesper > > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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