Hi Norman On Mon, Mar 1, 2021 at 4:38 AM Norman.Kern <norman.kern@xxxxxxx> wrote: > Hi, guys > > I am testing ceph on bcache devices, I found the performance is not good > as expected. Does anyone have any best practices for it? Thanks. > I've used bcache quite a bit with Ceph with the following configuration options tweaked a) use writeback mode rather than writethrough (which is the default) This ensures that the cache device is actually used for write caching b) turn off the sequential cutoff sequential_cutoff = 0 This means that sequential writes will also always go to the cache device rather than the backing device c) disable the congestion read and write thresholds congested_read_threshold_us = congested_write_threshold_us = 0 The following repository: https://git.launchpad.net/charm-bcache-tuning/tree/src/files has a python script and systemd configuration todo b) and c) automatically on all bcache devices on boot; a) we let the provisioning system take care of. HTH > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
 |