[PIG-4580] Fix TestTezAutoParallelism.testSkewedJoinIncreaseParallelism test failure

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.15.0
• Component/s: tez
• Hadoop Flags: Reviewed
• Assignee: Daniel Dai
• Reporter: Daniel Dai
• Created: 01/Jun/15 02:22
• Updated: 07/Jun/15 03:47
• Resolved: 01/Jun/15 17:43

Description

If a vertex need to increase parallelism dynamically, it cannot has additional broadcast input. In the test case, join vertex requires a broadcast edge to acquire sample file (used in IsFirstReduceOfKeyTez), and the join vertex use PartitionerDefinedVertexManager which can increase parallelism dynamically. If that happens, we will see exception:

Fetch failed:java.lang.IndexOutOfBoundsException
	at java.nio.Buffer.checkIndex(Buffer.java:532)
	at java.nio.ByteBufferAsLongBufferB.get(ByteBufferAsLongBufferB.java:115)
	at org.apache.tez.runtime.library.common.sort.impl.TezSpillRecord.getIndex(TezSpillRecord.java:101)
	at org.apache.tez.runtime.library.common.shuffle.Fetcher.getTezIndexRecord(Fetcher.java:596)
	at org.apache.tez.runtime.library.common.shuffle.Fetcher.doLocalDiskFetch(Fetcher.java:537)
	at org.apache.tez.runtime.library.common.shuffle.Fetcher.setupLocalDiskFetch(Fetcher.java:518)
	at org.apache.tez.runtime.library.common.shuffle.Fetcher.callInternal(Fetcher.java:191)
	at org.apache.tez.runtime.library.common.shuffle.Fetcher.callInternal(Fetcher.java:70)
	at org.apache.tez.common.CallableWithNdc.call(CallableWithNdc.java:36)
	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:745)

The fix disable dynamic parallelism if there is a broadcast edge (including sample file in skewed outer join, scalar followed by skewed join/order by). Also in inner skewed join, the sample file is not needed in join vertex, so it is not necessarily to broadcast it thus disable dynamic parallelism.

Issue Links

• is broken by: PIG-4377 Skewed outer join produce wrong result if a key is oversampled