I see. Thanks Chetan.
The functionality of the END_STREAM tuple does not seem to represent the
end of a stream. What was the reason behind the choice of this name?

David
On Dec 8, 2015 1:27 AM, "Chetan Narsude (cnarsude)" <[email protected]>
wrote:

> David,
>
>   When it emits END_STREAM, WindowIdActivatedReservoir is replaced with
> the reservoir which's active for all the (subsequent) windows. The logic
> you quoted below works hand in hand with the END_STREAM handling in the
> GenericNode. So during recovery, GenericNode will always see it as the
> first tuple but the operator itself or downstream Nodes will never see it.
>
> Not sure what you mean by:
> >Is it safe to treat the END_STREAM tuple just as RESET_TUPLE at recovery
> >from a checkpoint?
>
> ‹
> Chetan
>
>
>
> On 12/7/15, 5:37 PM, "David Yan" <[email protected]> wrote:
>
> >I traced to this piece of code in WindowIdActivatedReservoir.java below.
> >Chetan, please let me know if you recall the idea behind this.  The commit
> >message of the EndStreamTuple constructor call says something about making
> >a recovery test pass.
> >
> >@Override
> >public Tuple sweep()
> >{
> >  Tuple t;
> >  while ((t = reservoir.sweep()) != null) {
> >    if (t.getType() == MessageType.BEGIN_WINDOW && t.getWindowId() >
> >windowId) {
> >      reservoir.setSink(sink);
> >      return (est = new EndStreamTuple(windowId));
> >    }
> >    reservoir.remove();
> >  }
> >
> >  return null;
> >}
> >
> >On Mon, Dec 7, 2015 at 3:02 PM, David Yan <[email protected]> wrote:
> >
> >> Anybody have any idea?  Is it safe to treat the END_STREAM tuple just as
> >> RESET_TUPLE at recovery from a checkpoint?
> >>
> >> David
> >>
> >> On Fri, Dec 4, 2015 at 10:34 AM, David Yan <[email protected]>
> >>wrote:
> >>
> >>> Hi all,
> >>>
> >>> At recovery from a checkpoint, I see END_STREAM control tuple as the
> >>> first tuple sent from upstream.  That seems a little counter intuitive
> >>> because a stream is actually starting.  Can someone shed some light on
> >>>this?
> >>>
> >>> Thanks!
> >>>
> >>> David
> >>>
> >>
> >>
>
>

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