Ceph pool Pg num

[yena]

Hello, is it correct a 256 Pg num for a
8 OSD 3/2 cluster ?
i have calculated:
(8x100)/3 = 266 ~ 256 pg

Question:
if in the next month i will add more OSD and nodes, i will have to migrate on a new Pool with different Pg num?

Thanks

 

[fireon]

http://ceph.com/pgcalc/

 

[udo]

Question:
if in the next month i will add more OSD and nodes, i will have to migrate on a new Pool with different Pg num?

Hi,
you can extend the PG count of an pool during run time (but do an lot of data movement, so the system should be calm as possible).
But you never can reduce an PG count - in this case you must create an new pool with less PGs and move the data.

Udo