As far as I know there is nothing hard coded in Cassandra that kicks in every 4 hours. Turn on GC logging, maybe dump the output of jstats to a file and correlate this data with the Cassandra logs. Cassandra logs are pretty good in telling you what is going on.
2013/12/10 Joel Samuelsson <samuelsson.j...@gmail.com> > Hello, > > We've been having a lot of problems with extremely long GC (and still do) > which I've asked about several times on this list (I can find links to > those discussions if anyone is interested). > We noticed a pattern that the GC pauses may be related to something > happening every 4 hours. Is there anything specific happening within > Cassandra with a 4 hour interval? > > Any help is much appreciated, > Joel Samuelsson >
