On 2020-10-25 15:20, Amudhan P wrote: > Hi, > > For my quick understanding How PG's are responsible for allowing space > allocation to a pool? > > My understanding that PG's basically helps in object placement when the > number of PG's for a OSD's is high there is a high possibility that PG > gets lot more data than other PG's. At this situation, we can use the > balance between OSD's. > > But, I can't understand the logic of how does it restrict space to a pool? The space available in the cluster is available for all pools that match the CRUSH rule. OSDs contain PGs which contain objects. With many PGs per OSD (100-200 depending on disk type) the balancer can optimize for equal placement of PGs, optimize for available space, or a mix of both. The amount of space available is determined by the fullest OSD, as that OSD will be the first to run out of space for new writes. The more PGs the more evenly they can be distributed accross the cluster and the lower the standard deviation will be. Gr. Stefan _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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