Hi Igor,
you're right indeed, the db volume is 100G in size for the hdd osds.
Knowing this, the actual raw use is 783G - 7x100G = 83G which is pretty close to the sum
of the files in the HDD pools times the pool size which is roughly 25x3=75G.
Thanks a lot for your explanation of this tiny but highly confusing detail.
Best
Georg
Igor Fedotov wrote:
> Hi Georg,
>
> I suspect your db device size is around 100GiB size? And actual total
> hdd class size is rather 700 GiB (100 GiBĀ * 7 osds) less than reported
> 19 TiB.
>
> Is the above correct? If so then high raw size(s) is caused by osd stats
> reporting design - it unconditionally includes full db volume size into
> reported total/used space.
>
> Hence one gets both "ceph df's" RAW STORAGE SIZE and "ceph osd
> df's"
> SIZE/RAW USE numbers increased.
>
>
> You might want to inspect per-pool usage sizes via "ceph df detail"
> command and highly likely they will show expected numbers.
>
>
> Thanks,
>
> Igor