Quoting Ignazio Cassano (ignaziocassano@xxxxxxxxx): > Hello All, > I installed ceph luminous with openstack, an using fio in a virtual machine > I got slow random writes: > > fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test > --filename=random_read_write.fio --bs=4k --iodepth=64 --size=4G > --readwrite=randrw --rwmixread=75 Do you use virtio-scsi with a SCSI queue per virtual CPU core? How many cores do you have? I suspect that the queue depth is hampering throughput here ... but is throughput performance really interesting anyway for your use case? Low latency generally matters most. Gr. Stefan -- | BIT BV https://www.bit.nl/ Kamer van Koophandel 09090351 | GPG: 0xD14839C6 +31 318 648 688 / info@xxxxxx _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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