On Wed, Oct 2, 2019 at 3:41 PM Paul Emmerich <paul.emmerich(a)croit.io> wrote:
On Wed, Oct 2, 2019 at 10:56 PM Robert LeBlanc <robert(a)leblancnet.us> wrote:
Is there a way to have leveldb compact more
frequently or cause it to
come up for air more frequently and respond to heartbeats and process
some IO?
you can manually trigger a compaction via the admin socket (or was it
via ceph tell?) with the compact command, but I don't think that this
helps with your workload.
This would be really helpful, I've just been restarting OSD processes.
After some digging, it looks like it was added to Luminous [1]. :(
I thought
splitting PGs would help, but we are still seeing
the problem (previously ~20 PGs per OSD to now ~150). I still have
some space on the SSDs that I can double, almost triple the journal,
but not sure if that will help in this situation.
no, a larger journal will not help for leveldb workloads.
Big difference between FileStore journals and BlueStore DB devices:
BlueStore actually puts all the metadata onto the SSD permanently, a
FileStore journal is just a journal (and 5 GB is large enough, it
won't use that much space for small operations like deletions).
(The answer that you don't want to hear is probably the best way
forward: upgrade to BlueStore)
We are planning to replace this cluster in ~6 months, so we don't want
to upgrade it. I'm just looking for things that I may have missed that
will keep the pager quieter until then.
[1]
https://bugzilla.redhat.com/show_bug.cgi?id=1441693
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Robert LeBlanc
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