[
https://issues.apache.org/jira/browse/CASSANDRA-13063?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15766516#comment-15766516
]
Sylvain Lebresne commented on CASSANDRA-13063:
----------------------------------------------
I doubt this has much noticeable impact in practice but there is definitively
no reason to create an object every time so happy if you want to provide a
patch. Using a {{ConcurrentHashMap}} is however quite heavy handed imo: we
support at best a handful of versions in any given release so I suggest
declaring them as static instances (or through an enum) and use a simple switch
to retrieve the proper object form the version string.
> Too many instances of BigVersion
> --------------------------------
>
> Key: CASSANDRA-13063
> URL: https://issues.apache.org/jira/browse/CASSANDRA-13063
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Simon Zhou
> Assignee: Simon Zhou
> Priority: Minor
>
> When debugging with Cassandra 3.0.10 I found 70+ BigVersion objects on a new
> node after . This was from a cluster created by CMM and had very little data.
> Since we create a new instance of BigVersion for each SSTable, that would
> create too many objects, eg, when bootstrapping new node in a cluster with
> many sstables.
> Looks like sstables can actually share the same BigVersion instance as long
> as they has same version. What we can do is to create a object cache and only
> create new object if not found.
> {code}
> ConcurrentHashMap<String, BigVersion> versions = new ConcurrentHashMap<>();
> {code}
> May not be a big deal but a minor improvement. [~tjake] what do you think?
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
