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https://issues.apache.org/jira/browse/CASSANDRA-6934?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13960445#comment-13960445
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Benedict commented on CASSANDRA-6934:
-------------------------------------
Initial patch available
[here|https://github.com/belliottsmith/cassandra/tree/6934]
Optimises to some extent the various compare() implementations for
AbstractCType, and at the same time slightly optimises compare in BTree to
avoid unwrapping the special +/-Inf values except when absolutely necessary,
and to perform (potentially) one fewer comparison per update() when not
updating identical values, and to not perform a wasteful start-of-range
compare() when _not_ inserting.
There are further performance improvements that can be made to
AbstractCType.compare() and its inheritors, but they're a little more invasive,
and since CASSANDRA-6694 will entail some optimisation work to make comparisons
less expensive, I will wait until then to do anything more.
I need to make some tweaks to stress so I can properly test the impact of this
patch on CQL, as there's no easy way to perform inserts of random columns. As
shown with CASSANDRA-6553, there is a marked improvement for simple composites,
and some quick and dirty benchmarking on my local box for thrift columns with
only the general purpose improvements showed a lesser but still marked impact.
> Optimise Byte + CellName comparisons
> ------------------------------------
>
> Key: CASSANDRA-6934
> URL: https://issues.apache.org/jira/browse/CASSANDRA-6934
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Benedict
> Assignee: Benedict
> Labels: performance
> Fix For: 2.1
>
>
> AbstractCompositeType is called a lot, so deserves some heavy optimisation.
> SimpleCellNameType can be optimised easily, but should explore other
> potential optimisations.
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