On Sat, Apr 4, 2020 at 4:13 PM <jesper@xxxxxxxx> wrote: > Offloading the block.db on NVMe / SSD: > https://docs.ceph.com/docs/mimic/rados/configuration/bluestore-config-ref/ > > Pro: Easy to deal with - seem heavily supported. > Con: As far as I can tell - this will only benefit the metadata of the > osd- not actual data. Thus a data-commit to the osd til still be dominated > by the writelatency of the underlying - very slow HDD. small writes (<= 32kb, configurable) are written to db first and written back to the slow disk asynchronous to the original request. -- Paul Emmerich Looking for help with your Ceph cluster? Contact us at https://croit.io croit GmbH Freseniusstr. 31h 81247 München www.croit.io Tel: +49 89 1896585 90 > > Bcache: > http://lists.ceph.com/pipermail/ceph-users-ceph.com/2018-June/027713.html > > Pro: Closest to the BBWC mentioned above - but with way-way larger cache > sizes. > Con: It is hard to see if I end up being the only one on the planet using > this > solution. > > Eat it - Writes will be as slow as hitting dead-rust - anything that > cannot live > with that need to be entirely on SSD/NVMe. > > Other? > > Thanks for your input. > > Jesper > _______________________________________________ > 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
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