I am new too but i had same question and this is my opinion (i would wait for other people to correct me or add more)
A1. I didn't find any formula but i believe 10 to 20G is more than enough for each OSD ( there are some variation like how long you going to hold data etc..) A2. basic rule is 5 OSD per SSD & ~15 OSD per NVMe SSD A3. I don't know Again bluestore is different if you have all SSD then you can keep WAL+DB on same disk ( Or if you have all SSD + NVMe then put WAL+DB in NVMe) On Thu, Aug 16, 2018 at 4:44 PM, Cody <codeology....@gmail.com> wrote: > Hi everyone, > > As a newbie, I have some questions about using SSD as the Bluestore > journal device. > > 1. Is there a formula to calculate the optimal size of partitions on > the SSD for each OSD, given their capacity and IO performance? Or is > there a rule of thumb on this? > > 2. Is there a formula to find out the max number of OSDs a single SSD > can serve for journaling? Or any rule of thumb? > > 3. What is the procedure to replace an SSD journal device used for > DB+WAL in a hot cluster? > > Thank you all very much! > > Cody > _______________________________________________ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com