[jira] [Commented] (TEZ-2237) BufferTooSmallException raised in UnorderedPartitionedKVWriter then DAG lingers

["Hitesh Shah (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/TEZ-2237?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14382873#comment-14382873 ] 

Hitesh Shah commented on TEZ-2237:
----------------------------------

Quick question [~cchepelov]: If "hadoop.TupleSerialization$SerializationElementWriter" catching the exception and then not re-throwing the error up to exit from Processor::run() ? 

> BufferTooSmallException raised in UnorderedPartitionedKVWriter then DAG lingers
> -------------------------------------------------------------------------------
>
>                 Key: TEZ-2237
>                 URL: https://issues.apache.org/jira/browse/TEZ-2237
>             Project: Apache Tez
>          Issue Type: Bug
>    Affects Versions: 0.6.0
>         Environment: Debian Linux "jessie"
> OpenJDK Runtime Environment (build 1.8.0_40-internal-b27)
> OpenJDK 64-Bit Server VM (build 25.40-b25, mixed mode)
> 7 * Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz, 16/24 GB RAM per node, 1*system disk + 4*1 or 2 TiB HDD for HDFS & local  (on-prem, dedicated hardware)
> Scalding 0.13.1 modified with https://github.com/twitter/scalding/pull/1220 to run Cascading 3.0.0-wip-90 with TEZ 0.6.0
>            Reporter: Cyrille Chépélov
>         Attachments: appmaster____syslog_dag_1427282048097_0215_1.red.txt.gz, appmaster____syslog_dag_1427282048097_0237_1.red.txt.gz, syslog_attempt_1427282048097_0215_1_21_000014_0.red.txt.gz, syslog_attempt_1427282048097_0237_1_70_000028_0.red.txt.gz
>
>
> On a specific DAG with many vertices (actually part of a larger meta-DAG), after about a hour of processing, several BufferTooSmallException are raised in UnorderedPartitionedKVWriter (about one every two or three spills).
> Once these exceptions are raised, the DAG remains indefinitely "active", tying up memory and CPU resources as far as YARN is concerned, while little if any actual processing takes place. 
> It seems two separate issues are at hand:
>   1. BufferTooSmallException are raised even though, small as the actually allocated buffers seem to be (around a couple megabytes were allotted whereas 100MiB were requested), the actual keys and values are never bigger than 24 and 1024 bytes respectively.
>   2. In the event BufferTooSmallExceptions are raised, the DAG fails to stop (stop requests appear to be sent 7 hours after the BTSE exceptions are raised, but 9 hours after these stop requests, the DAG was still lingering on with all containers present tying up memory and CPU allocations)
> The emergence of the BTSE prevent the Cascade to complete, preventing from validating the results compared to traditional MR1-based results. The lack of conclusion renders the cluster queue unavailable.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)