Hello Community Currently, I operate a CEPH Cluster utilizing Ceph Octopus version 1.5.2.7, installed through Ansible. The challenge I'm encountering is that, during scrubbing, OSD latency spikes to 300-600 ms, resulting in sluggish performance for all VMs. Additionally, some OSDs fail during the scrubbing process. In such instances, promptly halting the scrubbing resolves the issue. *Summary of CEPH Version*: CEPH Version Number of Nodes Node Networking OSD OSD Total pools PG Size 15.2.7 12 (6 SSD node + 6 HDD node) All nodes are connected through 10G bonded link, i.e. 10Gx2=20GB for each node. 64 SSD 42 HDD 106 one-ssd 256 active+clean one-hdd 512 active+clean cloudstack.hdd 512 active+clean I intend to enlarge the PG size for the "one-ssd" configuration. Please provide the PG number, and suggest the optimal approach to increase the PG size without causing any slowdown or service disruptions to the VMs. Your expertise and guidance on this matter would be highly valuable, and I'm eager to benefit from the collective knowledge of the Ceph community. Thank you in advance for your time and assistance. I look forward to hearing from you. *CEPH Health status:* root@mon1:~# ceph -s cluster: id: f8096ec7-51db-4557-85e6-57d7fdfe9423 health: HEALTH_WARN nodeep-scrub flag(s) set 656 pgs not deep-scrubbed in time services: mon: 3 daemons, quorum ceph2,mon1,ceph6 (age 4d) mgr: ceph4(active, since 2w), standbys: mon1, ceph3, ceph6, ceph1 mds: cephfs:1 {0=ceph8=up:active} 1 up:standby osd: 107 osds: 105 up (since 3h), 105 in (since 3d) flags nodeep-scrub rgw: 4 daemons active (ceph10.rgw0, ceph7.rgw0, ceph9.rgw0, mon1.rgw0) rgw-nfs: 2 daemons active (ceph7, ceph9) task status: data: pools: 13 pools, 2057 pgs objects: 9.40M objects, 35 TiB usage: 106 TiB used, 154 TiB / 259 TiB avail pgs: 2057 active+clean io: client: 14 MiB/s rd, 30 MiB/s wr, 1.50k op/s rd, 1.53k op/s wr root@ceph1:~# ceph df --- RAW STORAGE --- CLASS SIZE AVAIL USED RAW USED %RAW USED hdd 151 TiB 78 TiB 72 TiB 73 TiB 48.04 ssd 110 TiB 78 TiB 32 TiB 32 TiB 29.42 TOTAL 261 TiB 156 TiB 104 TiB 105 TiB 40.19 --- POOLS --- POOL ID PGS STORED OBJECTS USED %USED MAX AVAIL cephfs_data 1 64 3.8 KiB 0 11 KiB 0 23 TiB cephfs_metadata 2 8 228 MiB 79 685 MiB 0 23 TiB .rgw.root 3 32 6.0 KiB 8 1.5 MiB 0 23 TiB default.rgw.control 4 32 0 B 8 0 B 0 23 TiB default.rgw.meta 5 32 12 KiB 48 7.5 MiB 0 23 TiB default.rgw.log 6 32 4.8 KiB 207 6.0 MiB 0 23 TiB default.rgw.buckets.index 7 32 410 MiB 15 1.2 GiB 0 23 TiB default.rgw.buckets.data 8 512 4.6 TiB 1.29M 14 TiB 16.59 23 TiB default.rgw.buckets.non-ec 9 32 1.0 MiB 676 130 MiB 0 23 TiB one-hdd 10 512 9.2 TiB 2.45M 28 TiB 28.69 23 TiB device_health_metrics 11 1 9.5 MiB 113 28 MiB 0 23 TiB one-ssd 12 256 11 TiB 2.88M 32 TiB 31.37 23 TiB cloudstack.hdd 15 512 10 TiB 2.72M 31 TiB 30.94 23 TiB Regards Mosharaf Hossain Manager, Product Development IT Division Bangladesh Export Import Company Ltd. Level-8, SAM Tower, Plot #4, Road #22, Gulshan-1, Dhaka-1212,Bangladesh Tel: +880 9609 000 999, +880 2 5881 5559, Ext: 14191, Fax: +880 2 9895757 Cell: +8801787680828, Email: mosharaf.hossain@bol-online.com, Web: www.bol-online.com <https://www.google.com/url?q=http://www.bol-online.com&sa=D&source=hangouts&ust=1557908951423000&usg=AFQjCNGMxIuHSHsD3qO6y5JddpEZ0S592A>