[CASSANDRA-4153] Optimize truncate when snapshots are disabled or keyspace not durable

• Type: Improvement
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 1.1.1
• Assignee: Christian Spriegel
• Reporter: Christian Spriegel

Authors

Christian Spriegel

Reviewers

Jonathan Ellis

• Created: 15/Apr/12 00:51
• Updated: 16/Apr/19 09:32
• Resolved: 16/Apr/12 20:30

Description

My goal is to make truncate to be less IO intensive so that my junit tests run faster (as already explained in CASSANDRA-3710). I think I have now a solution which does not change too much:

I created a patch that optimizes three things within truncate:

• Skip the whole Commitlog.forceNewSegment/discardCompletedSegments, if durable_writes are disabled for the keyspace.
• With CASSANDRA-3710 implemented, truncate does not need to flush memtables to disk when snapshots are disabled.
• Reduce the sleep interval

The patch works nicely for me. Applying it and disabling durable_writes/autoSnapshot increased the speed of my testsuite vastly. I hope I did not overlook something.

Let me know if my patch needs cleanup. I'd be glad to change it, if it means the patch will get accepted.

Issue Links

• is related to: CASSANDRA-5704 add cassandra.unsafesystem property (Truncate flushes to disk again in 1.2, even with durable_writes=false)
• is related to: CASSANDRA-7511 Always flush on TRUNCATE
• relates to: CASSANDRA-3710 Add a configuration option to disable snapshots