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Hudson commented on HBASE-20542: -------------------------------- Results for branch master [build #386 on builds.a.o|https://builds.apache.org/job/HBase%20Nightly/job/master/386/]: (x) *{color:red}-1 overall{color}* ---- details (if available): (/) {color:green}+1 general checks{color} -- For more information [see general report|https://builds.apache.org/job/HBase%20Nightly/job/master/386//General_Nightly_Build_Report/] (/) {color:green}+1 jdk8 hadoop2 checks{color} -- For more information [see jdk8 (hadoop2) report|https://builds.apache.org/job/HBase%20Nightly/job/master/386//JDK8_Nightly_Build_Report_(Hadoop2)/] (x) {color:red}-1 jdk8 hadoop3 checks{color} -- For more information [see jdk8 (hadoop3) report|https://builds.apache.org/job/HBase%20Nightly/job/master/386//JDK8_Nightly_Build_Report_(Hadoop3)/] (/) {color:green}+1 source release artifact{color} -- See build output for details. (/) {color:green}+1 client integration test{color} > Better heap utilization for IMC with MSLABs > ------------------------------------------- > > Key: HBASE-20542 > URL: https://issues.apache.org/jira/browse/HBASE-20542 > Project: HBase > Issue Type: Sub-task > Components: in-memory-compaction > Reporter: Eshcar Hillel > Assignee: Eshcar Hillel > Priority: Major > Fix For: 3.0.0, 2.2.0 > > Attachments: HBASE-20542.branch-2.001.patch, > HBASE-20542.branch-2.003.patch, HBASE-20542.branch-2.004.patch, > HBASE-20542.branch-2.005.patch, HBASE-20542.master.003.patch, run.sh, > workloada, workloadc, workloadx, workloady > > > Following HBASE-20188 we realized in-memory compaction combined with MSLABs > may suffer from heap under-utilization due to internal fragmentation. This > jira presents a solution to circumvent this problem. The main idea is to have > each update operation check if it will cause overflow in the active segment > *before* it is writing the new value (instead of checking the size after the > write is completed), and if it is then the active segment is atomically > swapped with a new empty segment, and is pushed (full-yet-not-overflowed) to > the compaction pipeline. Later on the IMC deamon will run its compaction > operation (flatten index/merge indices/data compaction) in the background. > Some subtle concurrency issues should be handled with care. We next elaborate > on them. -- This message was sent by Atlassian JIRA (v7.6.3#76005)