Truncate really slow
I have two test clusters, both 2.0.15. One has a single node and one has three nodes. Truncate on the three node cluster is really slow, but is quite fast on the single-node cluster. My test cases truncate tables before each test, and 95% of the time in my test cases is spent truncating tables on the 3-node cluster. Auto-snapshotting is off. I know there’s some coordination that has to occur when a truncate happens, but it seems really excessive. Almost one second to truncate each table with an otherwise idle cluster. Any thoughts? Thanks in advance Robert
Re: Truncate really slow
Hi, you have to enable -Dcassandra.unsafesystem=true in cassandra-env.sh. Also disable durables writes for your CFs. This should speed things up and should reduce IOWait dramatically. kind regards, Christian On Wed, Jul 1, 2015 at 11:52 PM, Robert Wille rwi...@fold3.com wrote: I have two test clusters, both 2.0.15. One has a single node and one has three nodes. Truncate on the three node cluster is really slow, but is quite fast on the single-node cluster. My test cases truncate tables before each test, and 95% of the time in my test cases is spent truncating tables on the 3-node cluster. Auto-snapshotting is off. I know there’s some coordination that has to occur when a truncate happens, but it seems really excessive. Almost one second to truncate each table with an otherwise idle cluster. Any thoughts? Thanks in advance Robert
Re: Truncate really slow
On Wed, Jul 1, 2015 at 2:58 PM, horschi hors...@gmail.com wrote: you have to enable -Dcassandra.unsafesystem=true in cassandra-env.sh. Also disable durables writes for your CFs. This should speed things up and should reduce IOWait dramatically. The above two suggestions are almost always bad advice anywhere but in a test environment. =Rob
