Dmitriy,
Alexey's point is just an explanation of the existing implementation and not
how it is supposed to be. And while nobody really knows what the correct
behavior should be, the one implemented by Ignite is incredibly
over-engineered. As I argued in a different thread, other vendors provide more
reasonable implementations and their users seem to be quite content with the
performance.
Cheers
Andrey
> From: dsetrak...@gridgain.com
> Date: Thu, 3 Dec 2015 10:35:34 -0800
> Subject: Re: EntryProcessor invoked twice
> To: dev@ignite.apache.org
>
> Point taken.
>
> However I still don’t get why it should be called twice in PESSIMISTIC
> mode. Can someone explain?
>
> D.
>
> On Thu, Dec 3, 2015 at 10:04 AM, Andrey Gura <ag...@gridgain.com> wrote:
>
> > Hi,
> >
> > Recently Alexey Goncharuk wrote in thread "EntryProcessor execution
> > semantics":
> >
> > For example, in a case of explicit optimistic
> > > READ_COMMITTED transaction it may be called more than once because Ignite
> > > needs to calculate a return value for the first invoke() and then it
> > should
> > > be called second time during commit when transactional locks are held.
> >
> >
> > Current requirement is that an EntryProcessor should be a stateless
> > > function, and it may be called more than once (but of course it will
> > > receive the same cache value every time).
> > >
> >
> >
> >
> > On Thu, Dec 3, 2015 at 8:46 PM, Valentin Kulichenko <
> > valentin.kuliche...@gmail.com> wrote:
> >
> > > Dmitry,
> > >
> > > Counter will not be incremented twice, because the entry is locked and EP
> > > is guaranteed to be called both times for the same old value. So there is
> > > no critical bug here in my view, but I just don't see the reason why we
> > > call it two times instead of one for one operation.
> > >
> > > -Val
> > >
> > > On Thu, Dec 3, 2015 at 1:22 AM, Dmitriy Setrakyan <dsetrak...@apache.org
> > >
> > > wrote:
> > >
> > > > I think this is definitely a bug. Imagine that EP is used to maintain a
> > > > counter, and the counter is incremented with every update. In this case
> > > the
> > > > counter will be updated 2 times instead of 1.
> > > >
> > > > Alexey G., would be nice to hear your thoughts here.
> > > >
> > > > D.
> > > >
> > > > On Wed, Dec 2, 2015 at 9:08 PM, Valentin Kulichenko <
> > > > valentin.kuliche...@gmail.com> wrote:
> > > >
> > > > > Igniters,
> > > > >
> > > > > I noticed that when I execute cache.invoke() in transactional cache,
> > > it's
> > > > > invoked twice for the same old value on the primary node. First
> > > > invocation
> > > > > is done on prepare step [1], the second one happens on commit [2]. Is
> > > > this
> > > > > expected behavior? Why can't we reuse already calculated new value
> > > during
> > > > > commit?
> > > > >
> > > > > [1]
> > > > > java.lang.RuntimeException: XXX
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > com.workday.fabric.ScratchClient$ScratchEntryProcessor.process(ScratchClient.java:106)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > com.workday.fabric.ScratchClient$ScratchEntryProcessor.process(ScratchClient.java:96)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.onEntriesLocked(GridDhtTxPrepareFuture.java:381)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.prepare0(GridDhtTxPrepareFuture.java:909)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.mapIfLocked(GridDhtTxPrepareFuture.java:527)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.prepare(GridDhtTxPrepareFuture.java:822)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxLocal.prepareAsync(GridDhtTxLocal.java:462)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler.prepareNearTx(IgniteTxHandler.java:406)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler.prepareTx(IgniteTxHandler.java:200)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler.processNearTxPrepareRequest(IgniteTxHandler.java:101)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler$1.apply(IgniteTxHandler.java:114)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler$1.apply(IgniteTxHandler.java:112)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.processMessage(GridCacheIoManager.java:580)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.onMessage0(GridCacheIoManager.java:280)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.handleMessage(GridCacheIoManager.java:198)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.access$000(GridCacheIoManager.java:77)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager$1.onMessage(GridCacheIoManager.java:160)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager.processRegularMessage0(GridIoManager.java:811)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager.access$1500(GridIoManager.java:106)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager$5.run(GridIoManager.java:774)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> > > > > at java.lang.Thread.run(Thread.java:745)
> > > > >
> > > > > [2]
> > > > > java.lang.RuntimeException: XXX
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > com.workday.fabric.ScratchClient$ScratchEntryProcessor.process(ScratchClient.java:106)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > com.workday.fabric.ScratchClient$ScratchEntryProcessor.process(ScratchClient.java:96)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxAdapter.applyTransformClosures(IgniteTxAdapter.java:1314)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxLocalAdapter.userCommit(IgniteTxLocalAdapter.java:826)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxLocalAdapter.finish(GridDhtTxLocalAdapter.java:836)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxLocal.finish(GridDhtTxLocal.java:657)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxLocal.commitAsync(GridDhtTxLocal.java:557)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.onDone(GridDhtTxPrepareFuture.java:574)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.onDone(GridDhtTxPrepareFuture.java:95)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridCompoundFuture.checkComplete(GridCompoundFuture.java:260)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridCompoundFuture.access$700(GridCompoundFuture.java:43)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridCompoundFuture$Listener.apply(GridCompoundFuture.java:358)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridCompoundFuture$Listener.apply(GridCompoundFuture.java:302)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridFutureAdapter.notifyListener(GridFutureAdapter.java:262)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridFutureAdapter.notifyListeners(GridFutureAdapter.java:250)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridFutureAdapter.onDone(GridFutureAdapter.java:380)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridFutureAdapter.onDone(GridFutureAdapter.java:346)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.util.future.GridFutureAdapter.onDone(GridFutureAdapter.java:323)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture$MiniFuture.onResult(GridDhtTxPrepareFuture.java:1477)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.distributed.dht.GridDhtTxPrepareFuture.onResult(GridDhtTxPrepareFuture.java:454)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler.processDhtTxPrepareResponse(IgniteTxHandler.java:524)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler.access$200(IgniteTxHandler.java:87)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler$6.apply(IgniteTxHandler.java:144)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.transactions.IgniteTxHandler$6.apply(IgniteTxHandler.java:142)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.processMessage(GridCacheIoManager.java:580)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.onMessage0(GridCacheIoManager.java:280)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.handleMessage(GridCacheIoManager.java:198)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager.access$000(GridCacheIoManager.java:77)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.processors.cache.GridCacheIoManager$1.onMessage(GridCacheIoManager.java:160)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager.processRegularMessage0(GridIoManager.java:811)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager.access$1500(GridIoManager.java:106)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > org.apache.ignite.internal.managers.communication.GridIoManager$5.run(GridIoManager.java:774)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> > > > > at
> > > > >
> > > > >
> > > >
> > >
> > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> > > > > at java.lang.Thread.run(Thread.java:745)
> > > > >
> > > > > -Val
> > > > >
> > > >
> > >
> >
> >
> >
> > --
> > Andrey Gura
> > GridGain Systems, Inc.
> > www.gridgain.com
> >
