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From Chandni Singh <chan...@datatorrent.com>
Subject Re: Why is Async checkpointing made default?
Date Fri, 11 Dec 2015 17:36:29 GMT
Hi,

There hasn't been a close bracket here (borrowing Ram's expression :-) ).
>From what I see the majority agrees with making the fix.

Do we need to start a vote for this?

On Fri, Nov 27, 2015 at 3:00 PM, Thomas Weise <thomas@datatorrent.com>
wrote:

> Chetan,
>
> Would like to understand how the checkpointed callback helps you with what
> you indicated. This may require a specific example. Let's take it offline.
>
> Thomas
>
> On Wed, Nov 25, 2015 at 4:07 PM, Chetan Narsude (cnarsude) <
> cnarsude@cisco.com> wrote:
>
> > Yes - a few but cannot share the details - protected under NDA - ping me
> > in private and I can probably be able to give you more generic details on
> > similar cooked up examples.
> >
> >  The part that follows “e.g.” below is an example that probably is
> > sufficient to infer the use case logically, I think. I shared that to
> > exemplify how changing the semantics will break semver.
> >
> > —
> > Chetan
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > On 11/25/15, 3:51 PM, "Thomas Weise" <thomas@datatorrent.com> wrote:
> >
> > >Do you have a specific example?
> > >
> > >I see this happening in committed(), but not in checkpointed() where the
> > >checkpoint remains intermediate, whether it was copied to HDFS or not.
> > >
> > >
> > >On Wed, Nov 25, 2015 at 3:42 PM, Chetan Narsude (cnarsude) <
> > >cnarsude@cisco.com> wrote:
> > >
> > >> >
> > >> >Until we have this, how about we restore the previous behavior
> > >> >temporarily?
> > >> >Calling checkpointed() immediately does not seem to pose any
> practical
> > >> >issue but ensures that the code that was written under this
> assumption
> > >>is
> > >> >not broken.
> > >>
> > >> We can¹t do it. It would be incorrect. It breaks all the other code
> that
> > >> (unassumingly) correctly complied to the semantics. e.g. an operator
> > >>which
> > >> informs interesting parties that the checkpointed data is available
> for
> > >> immediate consumption from storage.
> > >>
> > >> ‹
> > >> Chetan
> > >>
> > >>
> >
> >
>

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