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https://issues.apache.org/jira/browse/PHOENIX-4010?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16082289#comment-16082289
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Ankit Singhal commented on PHOENIX-4010:
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One option (discussed internally with [~devaraj] and [~sergey.soldatov] ) is to
resend the hash table cache to the regionserver and re-execute the query again
for that particular region but one thing we see is that we need to hold hash
table caches at client during the course of the query(which may make client
memory vulnerable).
WDYT [~giacomotaylor]/[~enis] , @others any ideas?
Attaching the patch for the current option in meanwhile.
> Hash Join cache may not be send to all regionservers when we have stale HBase
> meta cache
> ----------------------------------------------------------------------------------------
>
> Key: PHOENIX-4010
> URL: https://issues.apache.org/jira/browse/PHOENIX-4010
> Project: Phoenix
> Issue Type: Bug
> Reporter: Ankit Singhal
> Assignee: Ankit Singhal
> Fix For: 4.12.0
>
> Attachments: PHOENIX-4010.patch
>
>
> If the region locations changed and our HBase meta cache is not updated then
> we might not be sending hash join cache to all region servers hosting the
> regions.
> ConnectionQueryServicesImpl#getAllTableRegions
> {code}
> boolean reload =false;
> while (true) {
> try {
> // We could surface the package projected
> HConnectionImplementation.getNumberOfCachedRegionLocations
> // to get the sizing info we need, but this would require a
> new class in the same package and a cast
> // to this implementation class, so it's probably not worth
> it.
> List<HRegionLocation> locations = Lists.newArrayList();
> byte[] currentKey = HConstants.EMPTY_START_ROW;
> do {
> HRegionLocation regionLocation =
> connection.getRegionLocation(
> TableName.valueOf(tableName), currentKey, reload);
> locations.add(regionLocation);
> currentKey = regionLocation.getRegionInfo().getEndKey();
> } while (!Bytes.equals(currentKey, HConstants.EMPTY_END_ROW));
> return locations;
> {code}
> Skipping duplicate servers in ServerCacheClient#addServerCache
> {code}
> List<HRegionLocation> locations =
> services.getAllTableRegions(cacheUsingTable.getPhysicalName().getBytes());
> int nRegions = locations.size();
>
> .....
> if ( ! servers.contains(entry) &&
> keyRanges.intersectRegion(regionStartKey,
> regionEndKey,
> cacheUsingTable.getIndexType() ==
> IndexType.LOCAL)) {
> // Call RPC once per server
> servers.add(entry);
> {code}
> For eg:- Table âTâ has two regions R1 and R2 originally hosted on
> regionserver RS1.
> while Phoenix/Hbase connection is still active, R2 is transitioned to RS2 ,
> but stale meta cache will still give old region locations i.e R1 and R2 on
> RS1 and when we start copying hash table, we copy for R1 and skip R2 as they
> are hosted on same regionserver. so, the query on a table will fail as it
> will unable to find hash table cache on RS2 for processing regions R2.
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