But this pg delete should happen on old osds not on the newly added ones, in my case almost all the newly added osds gots full (with what)? ________________________________ From: Konstantin Shalygin <[email protected]> Sent: Tuesday, May 27, 2025 3:30:49 PM To: Szabo, Istvan (Agoda) <[email protected]> Cc: Anthony D'Atri <[email protected]>; Anthony D'Atri <[email protected]>; Ceph Users <[email protected]> Subject: Re: [ceph-users] Newly added node osds getting full before rebalance finished
Email received from the internet. If in doubt, don't click any link nor open any attachment ! ________________________________ Hi, On 27 May 2025, at 10:54, Szabo, Istvan (Agoda) <[email protected]> wrote: Some status update, it's finished with 3x times stop and start the rebalance. Would be interesting to know what is the extra data generated on the new osds during remapped pg allocation at rebalance. I stopped when the osd reaches 89% full, I let it rest for 2 days, it went down to 64%. After restart filled up again to 89%, I stopped for a day and it went down to 71%, then final restart finished. I have some concerns regarding the PG allocator algorithm in Octopus—specifically, there may be issues either within the algorithm itself or potentially due to anomalous data generated during rebalancing. I'm not certain if this has been addressed or optimized in more recent releases. Currently, our maximum PG size is 60GB. However, during rebalancing, it appears that PGs are being allocated without a thorough check on their sizes. Upon reviewing the number of PGs on our OSDs, I’m seeing values between 60 and 70. This implies that if 60–70 PGs, each sized at 60GB, are assigned to a single OSD, the OSD will inevitably reach full capacity. A more balanced approach would be to distribute smaller PGs as well, not just the largest ones. It is possible that the balancer intervenes at a later stage but not when has remapped pgs, this is not entirely clear from the current behavior. In Octopus since this [1] patch, the OSD really care about RAW sizes. You should understand, that after PG moved to another OSD, - PG should switch her state to Stray. Only Stray PG's will be removed eventually. OSD delete one object in second for single PG. So, if you have many PG for remove and wanna increase delete speed you should look to the osd_delete_sleep_ option k [1] https://tracker.ceph.com/issues/50601 ________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses. _______________________________________________ ceph-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
