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Hive QA commented on HIVE-17684: -------------------------------- | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || || || || || {color:brown} Prechecks {color} || | {color:green}+1{color} | {color:green} @author {color} | {color:green} 0m 1s{color} | {color:green} The patch does not contain any @author tags. {color} | || || || || {color:brown} master Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 11m 18s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 40s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 1m 6s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 6m 10s{color} | {color:blue} ql in master has 2280 extant Findbugs warnings. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 26s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 1m 47s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 42s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 42s{color} | {color:green} the patch passed {color} | | {color:red}-1{color} | {color:red} checkstyle {color} | {color:red} 0m 57s{color} | {color:red} ql: The patch generated 11 new + 31 unchanged - 0 fixed = 42 total (was 31) {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s{color} | {color:green} The patch has no whitespace issues. {color} | | {color:red}-1{color} | {color:red} findbugs {color} | {color:red} 4m 20s{color} | {color:red} ql generated 1 new + 2279 unchanged - 1 fixed = 2280 total (was 2280) {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 56s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 13s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 32m 17s{color} | {color:black} {color} | \\ \\ || Reason || Tests || | FindBugs | module:ql | | | Write to static field org.apache.hadoop.hive.ql.exec.Operator.lastAlertGcTimePercentage from instance method org.apache.hadoop.hive.ql.exec.Operator$1.alert(GcTimeMonitor$GcData) At Operator.java:from instance method org.apache.hadoop.hive.ql.exec.Operator$1.alert(GcTimeMonitor$GcData) At Operator.java:[line 96] | \\ \\ || Subsystem || Report/Notes || | Optional Tests | asflicense javac javadoc findbugs checkstyle compile | | uname | Linux hiveptest-server-upstream 3.16.0-4-amd64 #1 SMP Debian 3.16.36-1+deb8u1 (2016-09-03) x86_64 GNU/Linux | | Build tool | maven | | Personality | /data/hiveptest/working/yetus_PreCommit-HIVE-Build-12815/dev-support/hive-personality.sh | | git revision | master / 87b9f64 | | Default Java | 1.8.0_111 | | findbugs | v3.0.0 | | checkstyle | http://104.198.109.242/logs//PreCommit-HIVE-Build-12815/yetus/diff-checkstyle-ql.txt | | findbugs | http://104.198.109.242/logs//PreCommit-HIVE-Build-12815/yetus/new-findbugs-ql.html | | modules | C: ql U: ql | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-12815/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > HoS memory issues with MapJoinMemoryExhaustionHandler > ----------------------------------------------------- > > Key: HIVE-17684 > URL: https://issues.apache.org/jira/browse/HIVE-17684 > Project: Hive > Issue Type: Bug > Components: Spark > Reporter: Sahil Takiar > Assignee: Misha Dmitriev > Priority: Major > Attachments: HIVE-17684.01.patch, HIVE-17684.02.patch, > HIVE-17684.03.patch > > > We have seen a number of memory issues due the {{HashSinkOperator}} use of > the {{MapJoinMemoryExhaustionHandler}}. This handler is meant to detect > scenarios where the small table is taking too much space in memory, in which > case a {{MapJoinMemoryExhaustionError}} is thrown. > The configs to control this logic are: > {{hive.mapjoin.localtask.max.memory.usage}} (default 0.90) > {{hive.mapjoin.followby.gby.localtask.max.memory.usage}} (default 0.55) > The handler works by using the {{MemoryMXBean}} and uses the following logic > to estimate how much memory the {{HashMap}} is consuming: > {{MemoryMXBean#getHeapMemoryUsage().getUsed() / > MemoryMXBean#getHeapMemoryUsage().getMax()}} > The issue is that {{MemoryMXBean#getHeapMemoryUsage().getUsed()}} can be > inaccurate. The value returned by this method returns all reachable and > unreachable memory on the heap, so there may be a bunch of garbage data, and > the JVM just hasn't taken the time to reclaim it all. This can lead to > intermittent failures of this check even though a simple GC would have > reclaimed enough space for the process to continue working. > We should re-think the usage of {{MapJoinMemoryExhaustionHandler}} for HoS. > In Hive-on-MR this probably made sense to use because every Hive task was run > in a dedicated container, so a Hive Task could assume it created most of the > data on the heap. However, in Hive-on-Spark there can be multiple Hive Tasks > running in a single executor, each doing different things. -- This message was sent by Atlassian JIRA (v7.6.3#76005)