Thanks for your fast reply! We just tried all four possible combinations of
bluefs_preextend_wal_files and bluefs_buffered_io, but the write-iops in test
"usecase1" remain the same. By the way bluefs_preextend_wal_files has been
false in 14.2.9 (as in 15.2.3). Any other ideas?
David Orman wrote:
> * bluestore: common/options.cc: disable bluefs_preextend_wal_files <--
> from 15.2.3 changelogs. There was a bug which lead to issues on OSD
> restart, and I believe this was the attempt at mitigation until a proper
> bugfix could be put into place. I suspect this might be the cause of the
> symptoms you're seeing.
>
>
https://tracker.ceph.com/issues/45613
>
https://github.com/ceph/ceph/pull/35293