> We are using 0.6.1, and are planning to upgrade to 0.6.6. Currently, we are > observing that the compaction is going at the rate about ~10MB per second. > We did not see obvious bottleneck hardware wise. > > > > Is this normal, or did we miss something?
Assuming you're otherwise not entirely saturating and hitting a bottleneck, likely your compaction is CPU bound in a single thread. Whether compaction will be CPU bound or disk bound will depend a lot on your data; in general, more smaller columns are more CPU intensive while fewer large columns will tend to be more disk bound. Unless you have a problem with compaction speed not staying caught up with write speeds, this is not necessarily bad as it limits the impact of compaction on disk I/O (i.e., less negative effects for real traffic assuming real traffic goes down to disk and isn't entirely in-memory). -- / Peter Schuller
