Cassandra will request a GC to free compacted SSTables if there is not sufficient space to write an SSTable or perform a compaction.
Aaron On 29 Mar 2011, at 02:15, Roberto Bentivoglio wrote: > Thanks you again, we're going to update our enviroment. > > Regards, > Roberto > > On 28 March 2011 17:08, Ching-Cheng Chen <cc...@evidentsoftware.com> wrote: > > AFAIK, setting gc_grace_period to 0 shouldn't cause this issue. In fact, > that what I'm using now in a single node environment like yours. > > However, I'm using 0.7.2 with some patches. If you are still using 0.7.0, > most likely you got hit with this bug. > You might want to patch it or upgrade to latest release. > > https://issues.apache.org/jira/browse/CASSANDRA-2059 > > Regards, > > Chen > Senior Developer, EvidentSoftware(Leaders in Monitoring of NoSQL & JAVA ) > http://www.evidentsoftware.com > > On Mon, Mar 28, 2011 at 11:04 AM, Roberto Bentivoglio > <roberto.bentivog...@gmail.com> wrote: > Hi Chen, > we've set the gc grace period of the column families to 0 as suggest in a > single node enviroment. > Can this setting cause the problem? I don't think so... > > Thanks, > Roberto > > On 28 March 2011 16:54, Ching-Cheng Chen <cc...@evidentsoftware.com> wrote: > tombstones removal also depends on your gc grace period setting. > > If you are pretty sure that you have proper gc grace period set and still on > 0.7.0, then probably related to this bug. > > https://issues.apache.org/jira/browse/CASSANDRA-2059 > > Regards, > > Chen > Senior Developer, EvidentSoftware(Leaders in Monitoring of NoSQL & JAVA ) > http://www.evidentsoftware.com > > On Mon, Mar 28, 2011 at 10:40 AM, Roberto Bentivoglio > <roberto.bentivog...@gmail.com> wrote: > Hi all, > we're working on a Cassandra 0.7.0 production enviroment with a store of data > near to 500 GB. > We need to periodically remove the tombstones from deleted/expired data > performing a major compaction operation through nodetool. > After invoking the compaction on a single column family we can see from > JConsole that the LiveSSTableCount is going from 15 to 3 while the > LiveDiskSpaceUsed is going from 90GB to 50GB. > The problem now is that the space on the file system is been taken from > Cassandra (I assumed from the old SSTable) and it isn't freed. We have tried > to perform a full GC from the JConsole as described in > http://wiki.apache.org/cassandra/MemtableSSTable without any success. The > space is freed only after a database restart. > > How can we free this disk space without restart the db? > > Thanks you very much, > Roberto Bentivoglio > > > >
