reading this:
"but when I add 2000 new titles with 300 rows each"
I'm thinking that you are over-partitioning your data....
I'm not sure exactly how that relates to the OOM error you are getting (it may 
not)....I'd test things out partitioning by date-only.... maybe date + 
title_type, but adding 2000+ dynamic partitions that each have 300 rows of data 
in them is asking for problems in Hive IMO...


From: Matt Olson [mailto:maolso...@gmail.com]
Sent: Friday, April 29, 2016 7:50 PM
To: user@hive.apache.org
Subject: Container out of memory: ORC format with many dynamic partitions

Hi all,

I am using Hive 1.0.1 and trying to do a simple insert into an ORC table, 
creating dynamic partitions. I am selecting from a table partitioned by dt and 
category, and inserting into a table partitioned by dt, title, and title_type. 
Other than the partitioning, the tables have the same schemas. Both title and 
title_type are fields in the first table, and when I insert into the second 
table, I am using them to create dynamic partitions. The .q file with the 
CREATE and INSERT statements is copied below.

SET hive.optimize.sort.dynamic.partition=true;
SET hive.exec.orc.memory.pool=1.0;
SET hive.exec.max.dynamic.partitions = 5000;
SET hive.exec.max.dynamic.partitions.pernode = 5000;
SET hive.merge.mapfiles = true;
SET mapred.min.split.size=134217728;
SET mapred.min.split.size.per.node=134217728;
SET mapred.min.split.size.per.rack=134217728;
SET mapred.output.compression.codec=com.hadoop.compression.lzo.LzoCodec;
SET mapred.map.output.compression.codec=com.hadoop.compression.lzo.LzoCodec;
SET mapred.max.split.size=134217728;
SET hive.map.aggr.hash.percentmemory=0.125;
SET hive.exec.parallel=true;
SET hive.exec.compress.intermediate=true;
SET hive.exec.compress.output=true;
SET mapred.map.child.java.opts=-Xmx2048M;
SET mapred.child.java.opts=-Xmx2048M;
SET mapred.task.profile=false;

CREATE EXTERNAL TABLE IF NOT EXISTS dynamic_partition_table (
field1 string,
field2 string,
...
field26 string
)
PARTITIONED BY (dt string, title string, title_type string)
STORED AS ORC
LOCATION '/hive/warehouse/partitioned_table'
TBLPROPERTIES ("orc.compress.size"="16000");

INSERT OVERWRITE TABLE dynamic_partition_table PARTITION (dt="2016-04-05", 
title, title_type)
SELECT
field1,
field2,
...
title,
title_type
FROM original_table
WHERE dt = "2016-04-05";

The original table has about 250 GB of data for 2016-04-05, and about 260 
different titles (some titles have very little data, some have ~20 GB). There 
is generally only one title_type per title. The INSERT action succeeds on that 
data set, but when I add 2000 new titles with 300 rows each to the original 
table, I get the following error during the INSERT:


Container [pid=6278,containerID=container_e26_1460661845156_49295_01_000244] is 
running beyond physical memory limits. Current usage: 2.2 GB of 2 GB physical 
memory used; 2.7 GB of 4.2 GB virtual memory used. Killing container.

I've found a couple questions online about this same error message for ORC 
files with lots of dynamic partitions, on an older version of Hive:
https://qnalist.com/questions/4836037/hive-0-12-orc-heap-issues-on-write

Based on that and the information about configuration properties at 
https://cwiki.apache.org/confluence/display/Hive/Configuration+Properties#ConfigurationProperties-ORCFileFormat,
 I have tried setting hive.exec.orc.memory.pool=1.0 in order to give as much 
heap space as possible to the ORC file writers. As you can see from the CREATE 
TABLE statement, I also decreased the orc.compress.size from the default 256 kb 
to 16 kb. After making these changes, the INSERT is still failing with the 
"beyond physical memory limits" error.

I've tried inserting into a table stored as RCFile rather than ORC, and in that 
case the action succeeds even with the additional 2000 titles.

Can anyone explain how exactly the two ORC parameters above affect the writing 
of dynamic partitions in ORC files, and why I'm not getting the OOM error when 
I use the RCFile format instead?  I'd also appreciate any suggestions for other 
tuning I could do to fix the memory management when using ORC.

Thanks for any help,
Matt

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