> 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. Now, that sounds really interesting - I havent been able to find that in the documentation - can you provide a pointer? Whats the configuratoin parameter named? Meaning moving block.dk to a say 256GB NVMe will do "the right thing" for the system and deliver a fast write cache for smallish writes. Would setting the parameter til 1MB be "insane"? Jesper _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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