[
https://issues.apache.org/jira/browse/PHOENIX-5313?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16868191#comment-16868191
]
Hadoop QA commented on PHOENIX-5313:
------------------------------------
{color:red}-1 overall{color}. Here are the results of testing the latest
attachment
http://issues.apache.org/jira/secure/attachment/12972269/PHOENIX-5313-v1.patch
against master branch at commit 1f2508dbde365aaedac628c89df237e8b6b46df8.
ATTACHMENT ID: 12972269
{color:green}+1 @author{color}. The patch does not contain any @author
tags.
{color:green}+1 tests included{color}. The patch appears to include 7 new
or modified tests.
{color:green}+1 javac{color}. The applied patch does not increase the
total number of javac compiler warnings.
{color:red}-1 release audit{color}. The applied patch generated 2 release
audit warnings (more than the master's current 0 warnings).
{color:green}+1 lineLengths{color}. The patch does not introduce lines
longer than 100
{color:green}+1 core tests{color}. The patch passed unit tests in .
Test results:
https://builds.apache.org/job/PreCommit-PHOENIX-Build/2689//testReport/
Release audit warnings:
https://builds.apache.org/job/PreCommit-PHOENIX-Build/2689//artifact/patchprocess/patchReleaseAuditWarnings.txt
Console output:
https://builds.apache.org/job/PreCommit-PHOENIX-Build/2689//console
This message is automatically generated.
> All mappers grab all RegionLocations from .META
> -----------------------------------------------
>
> Key: PHOENIX-5313
> URL: https://issues.apache.org/jira/browse/PHOENIX-5313
> Project: Phoenix
> Issue Type: Bug
> Reporter: Geoffrey Jacoby
> Assignee: Chinmay Kulkarni
> Priority: Major
> Attachments: PHOENIX-5313-v1.patch
>
> Time Spent: 0.5h
> Remaining Estimate: 0h
>
> Phoenix's MapReduce integration lives in PhoenixInputFormat. It implements
> getSplits by calculating a QueryPlan for the provided SELECT query, and each
> split gets a mapper. As part of this QueryPlan generation, we grab all
> RegionLocations from .META
> In PhoenixInputFormat:getQueryPlan:
> {code:java}
> // Initialize the query plan so it sets up the parallel scans
> queryPlan.iterator(MapReduceParallelScanGrouper.getInstance());
> {code}
> In MapReduceParallelScanGrouper.getRegionBoundaries()
> {code:java}
> return
> context.getConnection().getQueryServices().getAllTableRegions(tableName);
> {code}
> This is fine.
> Unfortunately, each mapper Task spawned by the job will go through this
> _same_ exercise. It will pass a MapReduceParallelScanGrouper to
> queryPlan.iterator(), which I believe is eventually causing
> getRegionBoundaries to get called when the scans are initialized in the
> result iterator.
> Since HBase 1.x and up got rid of .META prefetching and caching within the
> HBase client, that means that not only will each _Job_ make potentially
> thousands of calls to .META, potentially thousands of _Tasks_ will each make
> potentially thousands of calls to .META.
> We should get a QueryPlan and setup the scans without having to read all
> RegionLocations, either by using the mapper's internal knowledge of its split
> key range, or by serializing the query plan from the client and sending it to
> the mapper tasks for use there.
> Note that MapReduce tasks over snapshots are not affected by this, because
> region locations are stored in the snapshot manifest.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
