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From Yakov Zhdanov <yzhda...@apache.org>
Subject Re: IGNITE-708
Date Tue, 01 Sep 2015 10:21:20 GMT
In my view, Alex has 100% understanding on what is hapenning. Let's remove
background exchange if partition map does not change. Gianfranco, I don't
think you should  account for transactions. Only updates to partition
topology matters. Younger nodes should send local updates to the oldest.
The oldest one should spread partitions after some delay buffering possible
updates or similar messages from other nodes.

Hope this helps!
On Sep 1, 2015 11:14, "Gianfranco Murador" <murador.gianfranco@gmail.com>
wrote:

> Hello Alexey,
> I mean 'local partition map'. I am trying to investigate the issue, and in
> fact,
> I need some clarification about the ticket. From my understanding, It is
> necessary to refresh the partitions (refreshPartitions())
> only if the local partition is changed, or if a transaction has been made
> on it. So if I understand I need to add logic and control
> in the OnTimeOut method of the inner class . Is it correct ?
>
> /** {@inheritDoc} */
> @Override public void onTimeout() {
> cctx.kernalContext().closure().runLocalSafe(new Runnable() {
> @Override public void run() {
> if (!busyLock.readLock().tryLock())
> return;
>
> try {
>            // onTimeOut we refresh always the partitions
>       if (started.compareAndSet(false, true))
> refreshPartitions();
> }
> finally {
> busyLock.readLock().unlock();
>
> cctx.time().removeTimeoutObject(ResendTimeoutObject.this);
>
> pendingResend.compareAndSet(ResendTimeoutObject.this, null);
> }
> }
> });
> }
>
> Thank you, Regards, Gianfranco
>
> 2015-09-01 3:30 GMT+02:00 Dmitriy Setrakyan <dsetrakyan@apache.org>:
>
> > On Mon, Aug 31, 2015 at 5:57 PM, Alexey Goncharuk <
> > alexey.goncharuk@gmail.com> wrote:
> >
> > > As far as I understood Yakov's point, even this message indicating that
> > no
> > > change happened is redundant because we have message delivery
> guarantees
> > on
> > > communication level and no messages can be lost. If a node is waiting
> > for a
> > > message and receives a message indicating that no change had happened,
> I
> > am
> > > not even sure how this node should react: it means that the message
> with
> > an
> > > important update somehow was not received (a bug in the code?) and the
> > next
> > > message indicates that no updates after the lost message were made.
> > >
> >
> > I still would wait for a No-Change empty partition exchange message,
> rather
> > than have no message at all (and wait for a timeout?).
> >
> > Yakov, can you please chime in and let us all know what you meant by that
> > ticket?
> >
> >
> > >
> > > 2015-08-31 17:33 GMT-07:00 Dmitriy Setrakyan <dsetrakyan@apache.org>:
> > >
> > > > On Mon, Aug 31, 2015 at 4:58 PM, Alexey Goncharuk <
> > > > alexey.goncharuk@gmail.com> wrote:
> > > >
> > > > > Gianfranco,
> > > > >
> > > > > What do you mean by 'local cache' here?
> > > > >
> > > > > If you are talking about the local partition map, I do not think
we
> > > have
> > > > > such a method. The background exchange that is described in the
> > ticket
> > > is
> > > > > handled in controlled by the ResendTimeoutObject inner class in
> > > > > GridCachePartitionExchangeManager. I cannot recall any cases when
> > this
> > > > > exchange would be needed from the top of my head, but it looks like
> > you
> > > > > need to do some investigation and code digging to check whether the
> > > > > background exchange can be indeed safely removed :)
> > > > >
> > > >
> > > > Alexey, I actually think that this ticket is named wrongly. After
> > looking
> > > > at the description, it seems that Yakov is suggesting that we do not
> > send
> > > > the exchange message if there are no changes to the exchange.
> Perhaps,
> > we
> > > > should be still sending something indicating that no change happened,
> > > > otherwise, other nodes will hang forever waiting for the exchange to
> > > > complete.
> > > >
> > > > Am I wrong in my understanding?
> > > >
> > > >
> > > >
> > > > >
> > > > > 2015-08-28 5:58 GMT-07:00 Gianfranco Murador <murador@apache.org>:
> > > > >
> > > > > > Hi Igniters,
> > > > > > I 'm starting to implement this patch:
> > > > > > Can you tell me if there is already a convenient method to see
if
> > the
> > > > > local
> > > > > > cache was updated last time interval ?
> > > > > > Regards, Gianfranco
> > > > > >
> > > > > >
> > > > > > --
> > > > > > Gianfranco Murador
> > > > > > Igniter and Software Engineer.
> > > > > >
> > > > >
> > > >
> > >
> >
>

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