> I'm at 80%, so not quite panic yet ;-) > > I'm wondering, in the steady state, how much of the space used will > contain deleted data.
That depends entirely on your workload, including: * How big the data that you are deleting is in relation to the size of tombstones * How long the average piece of data lives before being deleted * How much other data never being deleted you have in relation to the data that gets deleted * How it varies over time and where you are in your "cycle" I can't offer any mathematics that will give you the actual answered for leveled compaction (and I don't have a good feel for it as I haven't used leveled compaction in production systems yet). It's strongly recommend graphing disk space for your particular workload/application and see how it behaves over time. And *have alerts* on disk space running out. Have a good amount of margin. Less so with leveled compaction than size tiered compaction, but still important. -- / Peter Schuller (@scode, http://worldmodscode.wordpress.com)
