Hi, It's observerd up to 10 times space is consumed when concurrent 200 files iozone writing test , with erasure code profile (k=8,m=4) data pool, mounted with ceph fuse, but disk usage is normal if only has one writing task . Furthermore everything is normal using replicated data pool, no matter how many writing operations at the same time. Regards, Dai #iozone -s 100M -r 1M -i 0 -u 200 -l 200 -+n -w ​ #df -h /data01 ceph-fuse on /data01 type fuse.ceph-fuse (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other) # du -sh /data01 801M /data01 #ceph df RAW STORAGE: CLASS SIZE AVAIL USED RAW USED %RAW USED hdd 357 TiB 356 TiB 60 GiB 132 GiB 0.04 ssd 1.3 TiB 1.3 TiB 2.6 GiB 5.6 GiB 0.42 TOTAL 358 TiB 358 TiB 62 GiB 137 GiB 0.04 POOLS: POOL ID STORED OBJECTS USED %USED MAX AVAIL meta_data01 1 166 MiB 64 509 MiB 0.04 423 GiB data_data01 2 800 MiB 201 8.9 GiB 0 226 TiB #ceph osd pool get data_data01 erasure_code_profile erasure_code_profile: profile_data01 #ceph osd erasure-code-profile get profile_data01 crush-device-class= crush-failure-domain=host crush-root=default jerasure-per-chunk-alignment=false k=8 m=4 plugin=jerasure technique=reed_sol_van w=8