[ceph-users] issue on adding SSD to SATA cluster for db/wal

Hi all, I have a 14.2.15 cluster with all SATA OSDs. Now we plan to add SSDs in the cluster for db/wal usage. I checked the docs and found a command 'ceph-bluestore-tool' can deal with the issue. I added db/wal to the osd in my test environment but in the end it still get the warning message. "osd.0 spilled over 64 KiB metadata from 'db' device (7 MiB used of 8.0 GiB) to slow device" my procedure : sdd is the new disk for db/wal. sgdisk --new=1:0:+8GB --change-name=1:bluestore_block_db_0 --partition-guid=1:$(uuidgen) --mbrtogpt -- /dev/sdd sgdisk --new=2:0:+1GB --change-name=2:bluestore_block_wal_0 --partition-guid=2:$(uuidgen) --mbrtogpt -- /dev/sdd systemctl stop ceph-osd@0 CEPH_ARGS="--bluestore-block-db-size 8589934592" ceph-bluestore-tool bluefs-bdev-new-db --path /var/lib/ceph/osd/ceph-0 --dev-target /dev/sdd1 ceph-bluestore-tool bluefs-bdev-new-wal --path /var/lib/ceph/osd/ceph-0/ --dev-target /dev/sdd2 ceph-bluestore-tool bluefs-bdev-expand --path /var/lib/ceph/osd/ceph-0/ systemctl start ceph-osd@0 ceph tell osd.0 compact The warning message tells that there is some metadata still in the slow device. How can I deal with this issue? Thanks