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Brandon Williams commented on CASSANDRA-7088: --------------------------------------------- My suggestion then is to turn on tracing, which will make it slower, but we'll be able to see what's going on post facto. > Massive performance degradation for TRUNCATE when migrating to 2.0 > ------------------------------------------------------------------ > > Key: CASSANDRA-7088 > URL: https://issues.apache.org/jira/browse/CASSANDRA-7088 > Project: Cassandra > Issue Type: Bug > Components: Core > Environment: Linux Mint 16 > Reporter: Jacek Furmankiewicz > Attachments: cassandra.yaml > > > We attempted to migrate our developers to Cassandra 2.0.7 from 1.2. > Everything worked perfectly, but we have experienced a massive drop in > developer velocity. > We run integration tests with Cucumber BDD and 1000 BDDs went from 7 minutes > (Cassandra 1.2) to 15 minutes (2.0.7), > This is when we run Cassandra of the ramdisk (/dev/shm) to make it run faster > on dev boxes. > When we tried pointed to actual drives the difference was dramatic: the > entire suite took over 70 minutes (!) vs 15 in Cassandra 1.2. > After investigation, we found that most of the time is spent in the > truncation logic between every scenario, where we truncate all the column > families and start with a clean DB for the next test case. > This used to be super fast in 1.2, is now very slow in 2.0. > It may not seem important, but upgrading to 2.0 has basically cut down > developer velocity by 100%, just by more than doubling the time it takes to > run our BDD suite. > We truncate the CFs using the Ruby driver: > $cassandra.column_families.each do |column_family| > name = column_family[0].to_s > $cassandra.truncate! name > end > I am attaching our cassandra.yaml. Please note we already switched off > auto_compaction before truncate, just as we did in 1.2 for dev boxes, Made no > difference. -- This message was sent by Atlassian JIRA (v6.2#6252)