This sounds more like an issue with query execution, rather than wrong
PRIMARY_SYNC
behavior. We already had a discussion about this optimization in replicated
cache and decided to switch it off by default.

-Val

On Tue, Apr 18, 2017 at 9:35 AM, Sergi Vladykin <sergi.vlady...@gmail.com>
wrote:

> With replicated cache we can execute a query against backup partitions that
> were not updated yet because of PRIMARY_SYNC. Thus we do not see an update.
>
> Sergi
>
> 2017-04-18 10:30 GMT+03:00 Dmitriy Setrakyan <dsetrak...@apache.org>:
>
> > Vladimir,
> >
> > What is wrong with a query in PRIMARY_SYNC mode? Why won't it work?
> >
> > D.
> >
> > On Tue, Apr 18, 2017 at 12:25 AM, Vladimir Ozerov <voze...@gridgain.com>
> > wrote:
> >
> > > Folks,
> > >
> > > I received a number of complaints from users that our default setting
> > favor
> > > performance at the cost of correctness and subtle behavior. Yesterday I
> > > faced one such situation on my own.
> > >
> > > I started REPLICATED cache on several nodes, put some data, executed
> > simple
> > > SQL and got wrong result. No errors, no warnings. The problem was
> caused
> > by
> > > default PRIMARY_SYNC mode. WTF, our cache doesn't work out of the box!
> > >
> > > Another widely known examples are data streamer behavior, "read form
> > > backups" + continuous queries.
> > >
> > > I propose to change our defaults to favor *correctness* over
> performance,
> > > and create good documentation and JavaDocs to explain users how to tune
> > our
> > > product. Proposed changes:
> > >
> > > 1) FULL_SYNC as default;
> > > 2) "readFromBackups=false" as default;
> > > 3) "IgniteDataStreamer.allowOverwrite=true" as default.
> > >
> > > Users should not think how to make Ignite work correctly. It should be
> > > correct out of the box.
> > >
> > > Vladimir.
> > >
> >
>

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