Hi, last week we had a "large omap" warning in one of our clusters. The affected object was 025-11-09T23:31:24.799+0000 7f70131b3640 0 log_channel(cluster) log [WRN] : Large omap object found. Object: 2:ddb71591:::mds1_openfiles.d:head PG: 2.89a8edbb (2.b) Key count: 200001 Size (bytes): 12122520 I wanted to get a deeper understanding on what triggers this specific issue and had a look at the code - I'm not that deep into C++, so please, correct me if I'm wrong. If I understand correctly, LARGE_OMAP warnings are only generated (and cleared) during deep-scrubs. If an object is found with more keys than osd_deep_scrub_large_omap_object_key_threshold, it will trigger the warning. In this case mds1_openfiles.d had a Key count of 200001 while this specific option got deep-scrubbed and that triggered the warning The MDS should create a new openfiles fragment when the threshold is reached. My question is: How exactly does the MDS end up with an openfiles segment with more than 200000? Shouldn't the MDS create a new segment as soon as the previous one reaches the configured limit? If this is considered a bug, I'm happy to open a report. Best regards Philipp -- Philipp Hocke Leiter Linux Systemadministration / Head Of TechOps CM4ALL GmbH Im Mediapark 6A - 50670 Köln / Cologne Phone +49-(0)221-6601-0 <https://outlook.office.com/mail/sentitems> Fax +49-(0)221-6601-1011 <https://outlook.office.com/mail/sentitems> E-Mail: philipp.hocke@cm4all.com Internet: www.cm4all.com