[
https://issues.apache.org/jira/browse/CASSANDRA-13271?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15886318#comment-15886318
]
Robert Stupp edited comment on CASSANDRA-13271 at 2/27/17 7:33 PM:
-------------------------------------------------------------------
The changes for {{ListType}} and {{SetType}} look good so far. However, you
miss some similar one in {{MapType}} and {{ReversedType}} plus the
corresponding {{List/Set/MapSerializer}} classes, that use the same pattern.
Can you provide a branch on GitHub instead of a patch file?
EDIT: Also {{DynamicCompositeType}}. You might also switch the pattern to
something like this:
{code}
X t t = internMap.get(key);
if (t == null)
internMap.computeIfAbsent(key, (key) -> ...);
{code}
In the rare case when an instance is missing, we can afford the extra overhead
but favor the cleaner code.
was (Author: snazy):
The changes for {{ListType}} and {{SetType}} look good so far. However, you
miss some similar one in {{MapType}} and {{ReversedType}} plus the
corresponding {{List/Set/MapSerializer}} classes, that use the same pattern.
Can you provide a branch on GitHub instead of a patch file?
> Reduce lock contention on instance factories of ListType and SetType
> --------------------------------------------------------------------
>
> Key: CASSANDRA-13271
> URL: https://issues.apache.org/jira/browse/CASSANDRA-13271
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: vincent royer
> Priority: Minor
> Labels: performance
> Fix For: 4.x
>
> Attachments:
> 0001-CASSANDRA-13271-singleton-factory-concurrency-opimiz.patch
>
>
> By doing some performance tests, i noticed that getInstance() in
> org.apache.cassandra.db.marshal.ListType and SetType could suffer from lock
> contention on the singleton factory getInstance(). Here is a proposal to
> reduce lock contention by using a ConcurrentMap and the putIfAbsent method
> rather than a synchronized method.
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
