On 2019-07-08T14:36:31, Maged Mokhtar <mmokhtar@xxxxxxxxxxx> wrote: Hi Maged, > Maybe not related, but we find with rbd, random 4k write iops start very low > at first for a new image and then increase over time as we write. If we > thick provision the image it work does not show this. This happens on random > small block and not sequential or large. Probably related to initial > obkect/chunk creation. I don't see that this is related, we actually see faster performance for random writes initially. (Unsurprising - writing to a non-existent part/object means the OSD has nothing else to read, so no overwrite.) > Also we use the default stripe width, maybe you try a pool with default > width and see if it is a factor. This is the default stripe_width for an EC pool with k=2. -- SUSE Linux GmbH, GF: Felix Imendörffer, Mary Higgins, Sri Rasiah, HRB 21284 (AG Nürnberg) "Experience is the name everyone gives to their mistakes." -- Oscar Wilde _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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