Hi Wesley, during spillover (or more precisely - during "no DB space" condition, DB spillovers tend to occur before) WAL allocations follow the same logic as DB ones - they are served from the main device. So WAL effectively keeps being in use but it allocates space from "slow" device. Thanks, Igor On 06.01.2025 19:46, Wesley Dillingham wrote:
I have a question for bluestore experts about the ability for an OSD to continue to make use of the WAL during spillover events when the WAL and DB were implicitly collocated as described here: https://docs.ceph.com/en/reef/rados/configuration/bluestore-config-ref/#devi...
" whenever a DB device is specified but an explicit WAL device is not, the WAL will be implicitly colocated with the DB on the faster device."
During DB spillover (happen because fast device's LV is out of space) does the WAL have some guaranteed allocation of space in the LV / assurance that it can use a fixed amount of space when in contention with the db or does the bluestore-OSD no longer have the ability to use the WAL during spillover?
I understand an admin could implement some workarounds to logically isolate and protect a wal and db on the same physical media but I am curious if such a mechanism exists already in the bluestore OSD itself. Thanks for the clarification.
Respectfully,
*Wes Dillingham* LinkedIn <http://www.linkedin.com/in/wesleydillingham> wes@wesdillingham.com _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io