[
https://issues.apache.org/jira/browse/CASSANDRA-20760?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Dmitry Konstantinov updated CASSANDRA-20760:
--------------------------------------------
Description:
Currently within org.apache.cassandra.db.memtable.TrieMemtable#getFlushSet we
iterate over all partitions to retrieve partition key sizes by constructing
byte[] for every partition key.
We can do a similar kind of traversal logic but only count bytes instead of
allocating and filling byte[] values. Additionally, we can skip token bytes
instead of parsing them.
!cpu_profile_before.png|width=1000!
when we do a flush we almost consume 1 cpu core for a second within getFlushSet:
!cpu_profile_before_pattern.png!
was:
Currently within org.apache.cassandra.db.memtable.TrieMemtable#getFlushSet we
iterate over all partitions to retrieve partition key sizes by constructing
byte[] for every partition key.
We can do a similar kind of traversal logic but only count bytes instead of
allocating and filling byte[] values. Additionally, we can skip token bytes
instead of parsing them.
!cpu_profile_before.png|width=1000!
> Optimize calculating of partition key sizes in TrieMemtable#getFlushSet
> -----------------------------------------------------------------------
>
> Key: CASSANDRA-20760
> URL: https://issues.apache.org/jira/browse/CASSANDRA-20760
> Project: Apache Cassandra
> Issue Type: Improvement
> Components: Local/Memtable
> Reporter: Dmitry Konstantinov
> Assignee: Dmitry Konstantinov
> Priority: Normal
> Fix For: 5.x
>
> Attachments: cpu_profile_after.png, cpu_profile_before.png,
> cpu_profile_before_pattern.png
>
>
> Currently within org.apache.cassandra.db.memtable.TrieMemtable#getFlushSet we
> iterate over all partitions to retrieve partition key sizes by constructing
> byte[] for every partition key.
> We can do a similar kind of traversal logic but only count bytes instead of
> allocating and filling byte[] values. Additionally, we can skip token bytes
> instead of parsing them.
> !cpu_profile_before.png|width=1000!
> when we do a flush we almost consume 1 cpu core for a second within
> getFlushSet:
> !cpu_profile_before_pattern.png!
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
