Many thanks! 

/Z

On Wed, 11 Oct 2023 at 12:51, Zac Dover <zac.dover@proton.me> wrote:
Zakhar,

I will take this matter to the Leadership Team. I will write to you within the week.

Zac Dover
Head of Upstream Documentation
Ceph Foundation

------- Original Message -------
On Wednesday, October 11th, 2023 at 7:10 PM, Zakhar Kirpichenko <zakhar@gmail.com> wrote:

Hi!

Not sure this question is a good fit for this mailing list, but the subject appears to be undocumented, and I'm not getting any response from ceph-users.

Monitors in our 16.2.14 cluster appear to quite often run "manual compaction" tasks, usually more than once per minute. During each compaction the monitor process writes approximately 500-600 MB of data to disk over a short period of time. These writes add up to tens of gigabytes per hour and hundreds of gigabytes per day, reducing .

Monitor rocksdb and compaction options are default:

"mon_compact_on_bootstrap": "false",
"mon_compact_on_start": "false",
"mon_compact_on_trim": "true",
"mon_rocksdb_options": "write_buffer_size=33554432,compression=kNoCompression,level_compaction_dynamic_level_bytes=true",

Where can I find some documentation regarding rocksdb usage by monitors? How can I ascertain where this is expected behavior, or whether this is something I can adjust?

I would appreciate your advice and/or direction towards the relevant documentation.

Best regards,
Zakhar