Hi all I am running Cassandra 1.0.10 installed from the apache debs on ubuntu 11.10 on a 7 node cluster.
I moved some tokens around my cluster and now have one node compacting a large Leveled compaction column family. It has done about 5k out of 10k outstanding compactions today. The other nodes have all finished. The weird thing is when it hits a big-ish chunk to compact, for example: pending tasks: 4555 compaction type keyspace column family bytes compacted bytes total progress Compaction Player PlayerDetail 213097 4286616517 0.00% , I see heap usage on it AND all other nodes go insane. Normal operation on all nodes is a leisurely saw-toothed climb to a CMS at just below 3/4 heap size every 10 minutes or so. During the big-ish compaction all nodes in the cluster CMS multiple times in a minute, with the peaks getting close to heap size. So my question is why does one node compacting put so much memory pressure on all the other nodes in the cluster and ruin my day?