On 22.10.21 11:29, Mevludin Blazevic wrote: > Dear Ceph users, > > I have a small Ceph cluster where each host consist of a small amount of SSDs > and a larger number of HDDs. Is there a way to use the SSDs as performance > optimization such as putting OSD Journals to the SSDs and/or using SSDs for > caching?
Hi, yes, SSDs can be put to good use as journal devices[0] for OSDs, or you could use them as caching devices for bcache[1]. This is actually a pretty widespread setup, theres docs for various scenarios[2][3] But be aware that OSD journals are pretty write-intense, so be sure to use fast, reliable SSDs (or NVMes). I have actually seen OSD performance (esp. latency and jitter) actually worsen with (prosumer-grade) SSDs that could not support the sustained write load. If at all in doubt run tests before putting prod on it [0] https://docs.ceph.com/en/latest/start/hardware-recommendations/ [1] https://bcache.evilpiepirate.org/ [2] https://charmhub.io/ceph-osd [3] https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/4/html/object_gateway_for_production_guide/using-nvme-with-lvm-optimally > Best regards, > Mevludin > _______________________________________________ ceph-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
