On Thu, Sep 22, 2011 at 9:27 AM, Roshan Dawrani <roshandawr...@gmail.com>wrote:
> Hi, > > We recently switched from Cassandra 0.7.2 to 0.8.5 and observing > considerable performance degradation in embedded server's response times > that we use in integration tests. > > One thing that we do is that we truncate our app column families after each > integration test so that the next one gets a new DB slate (wierd? but with > RDBMS that we used earlier, we just rolled back the transaction to get rid > of changes done in an integration test. CF truncation is a costly workaround > for that, which we will be very happy to avoid if anyone knows some trick). > > So, with the situation we are in, is anyone aware of any cassandra 0.8.5 > cofiguration that can be tweaked to at least get the performance we were > getting with 0.7.2? Exactly after the upgrade, our test execution times have > gone up at least by 60-70%. > > Some pointers please? > > Thanks. > > -- > Roshan > Blog: http://roshandawrani.wordpress.com/ > Twitter: @roshandawrani <http://twitter.com/roshandawrani> > Skype: roshandawrani > > 1) Should should try to dig in an determine why the truncate is slower. Look for related jira issues on truncation. Cassandra had some re-entrant code you could fork a JVM each test and use the CassandraServiceDataCleaner. (However multiple startups could end up causing more overhead then the truncation) I avoid this problem by using a different column family and or a different keyspaces for all my unit tests in a single class. Each class bring up a new embedded cluster and uses the data cleaner to sanitize the data directories. So essentially I never call truncate.
