autoscale_mode for pg is on for a particular pool (default.rgw.buckets.data) and EC 3-2 is used. During pool lifetime I've seen one time that PG number have changed automatically, but now I am also considering changing PG number manually after backfills completes. Right now pg_num 512 pgp_num 512 is used and I am considering to change it to 1024. Do you think that would be too aggressive maybe? Rok On Sun, Dec 22, 2024 at 8:46 PM Alwin Antreich <alwin.antreich@xxxxxxxx> wrote: > Hi Rok, > > On Sun, 22 Dec 2024 at 20:19, Rok Jaklič <rjaklic@xxxxxxxxx> wrote: > >> First I tried with osd reweight, waited a few hours then osd crush >> reweight, then with pg-umpap from Laimis. Seems to crush reweight was most >> effective, but not for "all" osds I tried. >> >> Uh, probably I've set ceph config set osd osd_max_backfills to high >> number in the past, probably better to reduce it to 1 in steps, since now >> much backfilling is already going on? >> > Every time a backfill finishes, a new one will be placed in the queue. The > number of backfills won't reduce as long as you don't lower it. You can > adjust it and see if it improves the backfill process or not (wait an hour > or two). > > >> >> Output of commands in attachment. >> > There seems to be a low amount of PGs for the rgw data pool, compared to > the amount of OSDs. Though it depends on the EC profile and size of a shard > (`ceph pg <id> query`) if this is really an issue. But in general the > amount of PGs is important, because too few of them will make them grow > larger. Hence backfilling a PG will take a longer time and easier tilts the > usage of OSDs, as the algorithm works by pseudo-randomly placing PGs and > not taking its size into account. > > I'd wait with the PG adjustment after the backfilling to the HDDs has > finished, should you need to adjust the number of PGs. As this will create > more data movement. > > Cheers, > Alwin > croit GmbH, https://croit.io/ > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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