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https://issues.apache.org/jira/browse/CASSANDRA-9754?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15592881#comment-15592881
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Michael Kjellman commented on CASSANDRA-9754:
---------------------------------------------

The large partitions hit 158GB today. Latencies are still stable and unchanged. 
Compaction backed up a little at one point but has fully caught up (with no 
change in actual write/read tps). I'm working very hard on a post 8099 version 
of the patch for trunk/3.0.x.

> 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: gc_collection_times_with_birch.png, 
> gc_collection_times_without_birch.png, gc_counts_with_birch.png, 
> gc_counts_without_birch.png, 
> perf_cluster_1_with_birch_read_latency_and_counts.png, 
> perf_cluster_1_with_birch_write_latency_and_counts.png, 
> perf_cluster_2_with_birch_read_latency_and_counts.png, 
> perf_cluster_2_with_birch_write_latency_and_counts.png, 
> perf_cluster_3_without_birch_read_latency_and_counts.png, 
> perf_cluster_3_without_birch_write_latency_and_counts.png
>
>
>  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?



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