Hey Patrick! Thanks, that's very insightful. We also have HDDs only and 25Gb/s ethernet between the machines, so similar to your setup, except we have >=8 disks per machine. Your workload seems more sequential than what I am expecting from our VMs, so maybe that favors EC for you. Out of curiosity, did you try the same benchmarks with 3x replication too? The raw numbers look promising, what I am seeing currently is about 350MB/s max sequential writes with the local RAID6's we have, which Ceph was able to saturate with a single OSD on a LV for testing. You already get about double of that, and we have twice as many disks, so should get even more. Have you tried 8+4 or 7+5 with 3 OSDs per host too? -- --------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------- Forschungszentrum Jülich GmbH 52425 Jülich Sitz der Gesellschaft: Jülich Eingetragen im Handelsregister des Amtsgerichts Düren Nr. HR B 3498 Vorsitzender des Aufsichtsrats: MinDir Stefan Müller Geschäftsführung: Prof. Dr. Astrid Lambrecht (Vorsitzende), Dr. Stephanie Bauer (stellvertretende Vorsitzende), Prof. Dr. Ir. Pieter Jansens, Prof. Dr. Laurens Kuipers --------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------