So, I see the recommendation for 4% of OSD space for blocks.db/WAL and the corresponding discussion regrading the 3/30/300GB vs 6/60/600GB allocation.
How does this change when WAL is seperate from blocks.db?
Reading [0] it seems that 6/60/600 is not correct. It seems that to compact a 300GB DB, you taking values from the above layer (which is only 10% of the lower layer and only some percentage that exceeds the trigger point of that will be merged down) and merging that in, so at worse case you would need 333GB (300+30+3) plus some headroom.
[0]
https://github.com/facebook/rocksdb/wiki/Leveled-Compaction
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Robert LeBlanc
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Robert LeBlanc
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