Caleb Rackliffe created CASSANDRA-20129:
-------------------------------------------
Summary: Restore optimization in MultiCBuilder around building one
clustering
Key: CASSANDRA-20129
URL: https://issues.apache.org/jira/browse/CASSANDRA-20129
Project: Apache Cassandra
Issue Type: Bug
Components: Legacy/Local Write-Read Paths
Reporter: Caleb Rackliffe
Assignee: Caleb Rackliffe
Back in CASSANDRA-10409, we optimized the single clustering case for
{{MultiCBuilder}} to produce less garbage. In CASSANDRA-19341, we de-facto
removed that optimization, and I'm seeing increased allocations in trunk,
specifically at least double the number of {{BTree}} builders. In the
write-heavy workload I'm profiling, this jumps up to become the most common
TLAB allocation. I'm attaching JFR screenshots from 4.1 and trunk that show the
codepaths that touch this on both versions. We should consider reintroducing
something like the old {{OneClusteringBuilder}}.
I used {{WriteBench}} to explore things here, mostly w/ the TRUNCATE {{EndOp}},
and made sure commitlog writes, view updates, and
{{CassandraTableWriteHandler}} tracing were disabled to reduce the noise.
[~blerer]
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
