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https://issues.apache.org/jira/browse/CASSANDRA-18248?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17696079#comment-17696079
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Benedict Elliott Smith commented on CASSANDRA-18248:
----------------------------------------------------
If looking at improving performance of query building - which I think we
_should_ do, as there are cases where it causes problems - it would be nice to:
1. Remove String.format calls, e.g.
[here|https://github.com/apache/cassandra/blob/530bc10bd0a053f5dcd8439fd3f5c72cd7952ea6/src/java/org/apache/cassandra/cql3/Tuples.java#L51]
2. Memoize `AbstractType.toString` as we invoke it in
`ResultSet.computeResultMetadataId`
For non-prepared statement workloads these show up _very clearly_ in traces,
which was noticed in some internal testing of Accord that wasn't preparing its
statements.
I would say that, regarding the use of streams, is that it is _less_ idiomatic
to use streams than to not, and that replacing simple streams with simple loops
should not be a very contentious change. Though I agree that in query parsing
they may not be very impactful, were I to write query parsing code from scratch
I would expect streams not to be used - query parsing _is_ hot code in my
opinion, e.g. when the parsed statement cache overflows due to user workloads.
> Consider avoiding streams on query building
> -------------------------------------------
>
> Key: CASSANDRA-18248
> URL: https://issues.apache.org/jira/browse/CASSANDRA-18248
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Berenguer Blasi
> Priority: Normal
> Labels: low-hanging-fruit
>
> During the review of CASSANDRA-18068 it was discussed whether preparing
> queries might be considered a hot path or not. Seen in isolation it isn't.
> But given multi-tenancy setups i.e. and coming from the experience of seeing
> how prepare is used by some customers as per some bug reports this might not
> be 100% true
> Let's discuss here if removing streams would make any sense. Most rewrites I
> expect wouldn't impact readability. [~adelapena] took a first stab and
> compiled a first list of candidates:
> *
> [o.a.c.cql3/CQL3Type.java#L840|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/CQL3Type.java#L840]
> *
> [o.a.c.cql3/CQL3Type.java#L876|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/CQL3Type.java#L876]
> *
> [o.a.c.cql3/Lists.java#L133|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/Lists.java#L133]
> *
> [o.a.c.cql3/Sets.java#L123|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/Sets.java#L123]
> *
> [o.a.c.cql3/MultiColumnRelation.java#L225|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/MultiColumnRelation.java#L225]
> *
> [o.a.c.cql3/QueryProcessor.java#L481|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/QueryProcessor.java#L481]
> *
> [o.a.c.cql3/TokenRelation.java#L138|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/TokenRelation.java#L138]
> *
> [o.a.c.cql3/conditions/ColumnConditions.java#L75|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/conditions/ColumnConditions.java#L75]
> *
> [o.a.c.cql3/functions/AbstractFunction.java#L69|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/functions/AbstractFunction.java#L69]
> *
> [o.a.c.cql3/functions/FunctionResolver.java#L203|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/functions/FunctionResolver.java#L203]
> *
> [o.a.c.cql3/functions/UDAggregate.java#L97|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/functions/UDAggregate.java#L97]
> *
> [o.a.c.cql3/restrictions/StatementRestrictions.java#L380|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/restrictions/StatementRestrictions.java#L380]
> *
> [o.a.c.cql3/selection/AbstractFunctionSelector.java#L72|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/AbstractFunctionSelector.java#L72]
> *
> [o.a.c.cql3/selection/MapSelector.java#L113|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/MapSelector.java#L113]
> *
> [o.a.c.cql3/selection/Selectable.java#L708|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/Selectable.java#L708]
> *
> [o.a.c.cql3/selection/Selectable.java#L793|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/Selectable.java#L793]
> *
> [o.a.c.cql3/selection/Selectable.java#L886|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/Selectable.java#L886]
> *
> [o.a.c.cql3/selection/Selectable.java#L954|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/Selectable.java#L954]
> *
> [o.a.c.cql3/selection/Selectable.java#L1024|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/selection/Selectable.java#L1024]
> *
> [o.a.c.cql3/statements/SelectStatement.java#L1278|https://github.com/apache/cassandra/blob/cassandra-4.1.0/src/java/org/apache/cassandra/cql3/statements/SelectStatement.java#L1278]
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