Hi, Recently I saw some strange behavior on one of the nodes of a 3-node cluster. A while ago I created a table and put some data (about 150M) in it for testing. A few days ago I started to import full data into that table using normal cql INSERT statements. As soon as inserting started, one node started non-stop full GC. The other two nodes were totally fine. I stopped the inserting process, restarted C* on all the nodes. All nodes are fine. But once I started inserting again, full GC kicked in on that node within a minute.The insertion speed is moderate. Again, the other two nodes were fine. I tried this process a couple of times. Every time the same node jumped into full GC. I even rebooted all the boxes. I checked system.log but found no errors or warnings before full GC started.
Finally I deleted and recreated the table. All of sudden the problem went away. The only thing I can think of is that table was created using STCS. After I inserted 150M data into it, I switched it to LCS. Then I ran incremental repair a couple of times. I saw validation and normal compaction on that table as expected. When I recreated the table, I created it with LCS. I don't have the problem any more but just want to share the experience. Maybe someone has an theory on this? BTW I am running C* 2.2.4 with CentOS 7 and Java 8. All boxes have the identical configurations. Thanks.
