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Prasanth Jayachandran commented on HIVE-20656: ---------------------------------------------- The configs seems to be changed by HIVE-20364 > Map aggregation memory configs are too aggressive > ------------------------------------------------- > > Key: HIVE-20656 > URL: https://issues.apache.org/jira/browse/HIVE-20656 > Project: Hive > Issue Type: Bug > Affects Versions: 4.0.0, 3.2.0 > Reporter: Prasanth Jayachandran > Priority: Major > > The defaults for the following configs seems to be too aggressive. In java > this can easily lead to several full GC pauses whose memory cannot be > reclaimed. > {code:java} > HIVEMAPAGGRHASHMEMORY("hive.map.aggr.hash.percentmemory", (float) 0.99, > "Portion of total memory to be used by map-side group aggregation hash > table"), > HIVEMAPAGGRMEMORYTHRESHOLD("hive.map.aggr.hash.force.flush.memory.threshold", > (float) 0.9, > "The max memory to be used by map-side group aggregation hash table.\n" + > "If the memory usage is higher than this number, force to flush > data"),{code} > > We can be little bit conservative for these configs to avoid getting into GC > pause. -- This message was sent by Atlassian JIRA (v7.6.3#76005)