[
https://issues.apache.org/jira/browse/CASSANDRA-9754?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15542043#comment-15542043
]
Branimir Lambov commented on CASSANDRA-9754:
--------------------------------------------
> Originally, I was mmapping 4kb aligned chunks as necessary.
Cassandra has some machinery to deal with the same problem in
{{RandomAccessReader}}; the solution we have in place is to map the entire file
in <2GB chunks and look the chunk up on a read. Take a look at
{{MmappedRegions}} in trunk and its users.
> Make index info heap friendly for large CQL partitions
> ------------------------------------------------------
>
> Key: CASSANDRA-9754
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9754
> Project: Cassandra
> Issue Type: Improvement
> Reporter: sankalp kohli
> Assignee: Michael Kjellman
> Priority: Minor
> Fix For: 4.x
>
> Attachments: 9754_part1-v1.diff, 9754_part2-v1.diff
>
>
> Looking at a heap dump of 2.0 cluster, I found that majority of the objects
> are IndexInfo and its ByteBuffers. This is specially bad in endpoints with
> large CQL partitions. If a CQL partition is say 6,4GB, it will have 100K
> IndexInfo objects and 200K ByteBuffers. This will create a lot of churn for
> GC. Can this be improved by not creating so many objects?
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
