On Sat, Jul 23, 2011 at 4:16 PM, Francois Richard <frich...@xobni.com> wrote: > My understanding is that during compaction cassandra does a lot of non > sequential readsa then dumps the results with a big sequential write.
Compaction reads and writes are both sequential, and 0.8 allows setting a MB/s to cap compaction at. As to the original question "do I need to add more machines" I'd say that depends more on whether your application's SLA is met, than what % io util spikes to. -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of DataStax, the source for professional Cassandra support http://www.datastax.com
