[ https://issues.apache.org/jira/browse/CASSANDRA-9754?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15578618#comment-15578618 ]
DOAN DuyHai commented on CASSANDRA-9754: ---------------------------------------- Stupid question: how are those improvement affect compaction ? Did you also monitor the compaction time during your benchmark tests and compare the time taken by each impl ? > 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? -- This message was sent by Atlassian JIRA (v6.3.4#6332)