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https://issues.apache.org/jira/browse/PHOENIX-3111?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Vincent Poon updated PHOENIX-3111:
----------------------------------
    Attachment: splitDuringUpsertSelect.patch

Here's a patch that has following tests to reproduce the issue, they're part of 
a larger suite I was writing to test global mutable secondary indexing:
testRegionCloseDuringUpsertSelect
testSplitDuringUpsertSelect

Patch includes something like what [~samarthjain] suggested - when a 
split/close has been requested, I throw IOException for any new incoming scans 
that require a write.  This at least allows the split/close to happen 
eventually, as the scansRefCounter won't go up, while still allowing for the 
existing operations in progress to finish.

The loop in preClose is rather dangerous, since if a scanner thread is 
interrupted, there is no guarantee the finally block will run, and so the 
scanRefCounter might never get back to 0.  I encountered this in the test when 
the miniCluster was attempting to shutdown, not sure if there are other 
scenarios where this might happen in actual production usage.  I throw an 
IOException during an interrupt there to avoid this.

Note that you currently can't run all the tests in the suite, so just run the 
individual tests you want to try.

> Possible Deadlock/delay while building index, upsert select, delete rows at 
> server
> ----------------------------------------------------------------------------------
>
>                 Key: PHOENIX-3111
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-3111
>             Project: Phoenix
>          Issue Type: Bug
>            Reporter: Sergio Peleato
>            Assignee: Rajeshbabu Chintaguntla
>            Priority: Critical
>             Fix For: 4.8.0
>
>         Attachments: PHOENIX-3111_addendum.patch, PHOENIX-3111.patch, 
> PHOENIX-3111_v2.patch, splitDuringUpsertSelect.patch
>
>
> There is a possible deadlock while building local index or running upsert 
> select, delete at server. The situation might happen in this case.
> In the above queries we scan mutations from table and write back to same 
> table in that case there is a chance of memstore might reach the threshold of 
> blocking memstore size then RegionTooBusyException might be thrown back to 
> client and queries might retry scanning.
> Let's suppose if we take a local index build index case we first scan from 
> the data table and prepare index mutations and write back to same table.
> So there is chance of memstore full as well in that case we try to flush the 
> region. But if the split happen in between then split might be waiting for 
> write lock on the region to close and flush wait for readlock because the 
> write lock in the queue until the local index build completed. Local index 
> build won't complete because we are not allowed to write until there is 
> flush. This might not be complete deadlock situation but the queries might 
> take lot of time to complete in this cases.
> {noformat}
> "regionserver//192.168.0.53:16201-splits-1469165876186" #269 prio=5 
> os_prio=31 tid=0x00007f7fb2050800 nid=0x1c033 waiting on condition 
> [0x0000000139b68000]
>    java.lang.Thread.State: WAITING (parking)
>         at sun.misc.Unsafe.park(Native Method)
>         - parking to wait for  <0x00000006ede72550> (a 
> java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync)
>         at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199)
>         at 
> java.util.concurrent.locks.ReentrantReadWriteLock$WriteLock.lock(ReentrantReadWriteLock.java:943)
>         at 
> org.apache.hadoop.hbase.regionserver.HRegion.doClose(HRegion.java:1422)
>         at 
> org.apache.hadoop.hbase.regionserver.HRegion.close(HRegion.java:1370)
>         - locked <0x00000006ede69d00> (a java.lang.Object)
>         at 
> org.apache.hadoop.hbase.regionserver.SplitTransactionImpl.stepsBeforePONR(SplitTransactionImpl.java:394)
>         at 
> org.apache.hadoop.hbase.regionserver.SplitTransactionImpl.createDaughters(SplitTransactionImpl.java:278)
>         at 
> org.apache.hadoop.hbase.regionserver.SplitTransactionImpl.execute(SplitTransactionImpl.java:561)
>         at 
> org.apache.hadoop.hbase.regionserver.SplitRequest.doSplitting(SplitRequest.java:82)
>         at 
> org.apache.hadoop.hbase.regionserver.SplitRequest.run(SplitRequest.java:154)
>         at 
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
>         at 
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
>         at java.lang.Thread.run(Thread.java:745)
>    Locked ownable synchronizers:
>         - <0x00000006ee132098> (a 
> java.util.concurrent.ThreadPoolExecutor$Worker)
> {noformat}
> {noformat}
> "MemStoreFlusher.0" #170 prio=5 os_prio=31 tid=0x00007f7fb6842000 nid=0x19303 
> waiting on condition [0x00000001388e9000]
>    java.lang.Thread.State: WAITING (parking)
>         at sun.misc.Unsafe.park(Native Method)
>         - parking to wait for  <0x00000006ede72550> (a 
> java.util.concurrent.locks.ReentrantReadWriteLock$NonfairSync)
>         at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireShared(AbstractQueuedSynchronizer.java:967)
>         at 
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireShared(AbstractQueuedSynchronizer.java:1283)
>         at 
> java.util.concurrent.locks.ReentrantReadWriteLock$ReadLock.lock(ReentrantReadWriteLock.java:727)
>         at 
> org.apache.hadoop.hbase.regionserver.HRegion.flushcache(HRegion.java:1986)
>         at 
> org.apache.hadoop.hbase.regionserver.HRegion.flush(HRegion.java:1950)
>         at 
> org.apache.hadoop.hbase.regionserver.MemStoreFlusher.flushRegion(MemStoreFlusher.java:501)
>         at 
> org.apache.hadoop.hbase.regionserver.MemStoreFlusher.flushRegion(MemStoreFlusher.java:471)
>         at 
> org.apache.hadoop.hbase.regionserver.MemStoreFlusher.access$800(MemStoreFlusher.java:75)
>         at 
> org.apache.hadoop.hbase.regionserver.MemStoreFlusher$FlushHandler.run(MemStoreFlusher.java:259)
>         at java.lang.Thread.run(Thread.java:745)
> {noformat}
> As a fix we need to block region splits if building index, upsert select, 
> delete rows running at server.
> Thanks [~sergey.soldatov] for the help in understanding the bug and analyzing 
> it. [~speleato] for finding it.



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