On Wed, 2 Aug 2017, McFarland, Bruce wrote: > I’m using SDD for the rocksdb/rockswal partitions and putting the data > on HDD’s. What is the recommended sizing for these partitions. I’ve read > various sizes discussed on the perf call and know that the code defaults > of 128MB for rocksdb is small and limits performance. What are the > recommended sizes for these partitions? tl;dr: 1GB for block.wal. For block.db, as much as you have. For an RBD-only pool, my guess is you want around 1-2% of your total storage, but I'm guessing... we need to deploy a real-ish RBD workload and see what the ratio is in practice. Mark can probably give us a worst-case value (after a long-running 4kb random-write workload). Omap data will go to block.db (if it will fit), so for RGW clusters there may be more. OTOH, the object metadata will be smaller (immutable objects, sequentially written), so it depends on how big your RGW objects are. We have no real-world data on this yet. sage
