[
https://issues.apache.org/jira/browse/CASSANDRA-9365?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
T Jake Luciani updated CASSANDRA-9365:
--------------------------------------
Description:
The main purpose of compaction is to keep reads fast by consolidating sstables
together to avoid merging on read.
In a cluster with many tables we currently treat all pending compaction as
equal. When in reality we may only be reading mainly from one of the tables.
Rather than FIFO we should prioritize access to the compactors based on read
activity. SStables per read might be a good metric. Also, we would need to be
sure to be fair to other tables over time. This would be a way to skew the
work towards the tables who need compaction the most.
It might also be nice to offer a nodetool command to kill specific compaction
jobs in progress that are not important under load.
was:
The main purpose of compaction is to keep reads fast by consolidating tables
together to avoid merging on read.
In a cluster with many tables we currently treat all pending compaction as
equal. When in reality we may only be reading mainly from one of the tables.
Rather than FIFO we should prioritize access to the compactors based on read
activity. SStables per read might be a good metric. Also, we would need to be
sure to be fair to other tables over time. This would be a way to skew the
work towards the tables who need compaction the most.
It might also be nice to offer a nodetool command to kill specific compaction
jobs in progress that are not important under load.
> Prioritize compactions based on read activity
> ---------------------------------------------
>
> Key: CASSANDRA-9365
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9365
> Project: Cassandra
> Issue Type: Improvement
> Reporter: T Jake Luciani
> Fix For: 3.x
>
>
> The main purpose of compaction is to keep reads fast by consolidating
> sstables together to avoid merging on read.
> In a cluster with many tables we currently treat all pending compaction as
> equal. When in reality we may only be reading mainly from one of the tables.
> Rather than FIFO we should prioritize access to the compactors based on read
> activity. SStables per read might be a good metric. Also, we would need to
> be sure to be fair to other tables over time. This would be a way to skew
> the work towards the tables who need compaction the most.
> It might also be nice to offer a nodetool command to kill specific compaction
> jobs in progress that are not important under load.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
