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From Sergi Vladykin <sergi.vlady...@gmail.com>
Subject Re: Off-Heap SQL Indexes
Date Fri, 04 Nov 2016 08:51:52 GMT
Denis,

I checked the code now as well. I actually was wrong, but your statement is
wrong either.

If we are talking about indexes then the exact condition when index will be
off-heap is the following: either setOffHeapMaxMemory >= 0 or setMemoryMode
is OFFHEAP_TIERED.

But if setMemoryMode is set to one of off-heap modes and setOffHeapMaxMemory is
-1, then setOffHeapMaxMemory is silently getting switched to 0.

Thus from the user standpoint we can say, that if either setOffHeapMaxMemory
>= 0 or setMemoryMode is set to any of off-heap modes, then indexes will go
off-heap.

Sergi

2016-11-04 6:30 GMT+03:00 Dmitriy Setrakyan <dsetrakyan@apache.org>:

> Do we currently throw an exception if memory mode is set to off-heap by the
> max-offheap-memory is set to "-1"? Otherwise, it can get very confusing to
> users.
>
> On Thu, Nov 3, 2016 at 10:22 AM, Denis Magda <dmagda@gridgain.com> wrote:
>
> > Sergi,
> >
> > Referring to your response and the source code I should say that, in
> fact,
> > the documentation has to state the following:
> >
> > “To place both data and indexes in off heap memory CacheConfiguration.
> setMemoryMode
> > has to be set to one of off heap modes and CacheConfiguration.
> setOffHeapMaxMemory
> > has to be set to a value different from -1 (disabled). If at least one of
> > these conditions is not met then both data and indexes will be located in
> > on heap memory”
> >
> > Is this statement correct?
> >
> > —
> > Denis
> >
> > > On Nov 3, 2016, at 2:53 AM, Sergi Vladykin <sergi.vladykin@gmail.com>
> > wrote:
> > >
> > > Prachi,
> > >
> > > In [2] we refer to the same CacheConfiguration.setOffHeapMaxMemory
> > > property, so [1] is correct. If setOffHeapMaxMemory is disabled (set to
> > > -1), then indexes will never be stored offheap, regardless of
> > setMemoryMode
> > > setting.
> > >
> > > Probably we have to change [2] to make it clear, that it is about
> > > setOffHeapMaxMemory
> > > but not about setMemoryMode.
> > >
> > > Sergi
> > >
> > >
> > > 2016-11-03 2:25 GMT+03:00 Prachi Garg <pgarg@gridgain.com>:
> > >
> > >> Engineers,
> > >>
> > >> I was going through documentation for Off-Heap SQL Indexes
> > >> <https://apacheignite.readme.io/docs/sql-queries#off-heap-sql-indexes
> >
> > and
> > >> found two contradicting statements-
> > >>
> > >> According to [1] -  " `CacheConfiguration.setOffHeapMaxMemory` is the
> > only
> > >> property to enable or disable off-heap indexing. While
> > >> CacheConfiguration.setMemoryMode is used to configure off-heap memory
> > >> <https://apacheignite.readme.io/v1.7/docs/off-heap-memory>, it does
> not
> > >> have any effect on indexing."
> > >>
> > >> According to [2] -  "Note that when off-heap memory is configured,
> > Ignite
> > >> will store query indexes off-heap as well."
> > >>
> > >>
> > >> Which one is true?
> > >>
> > >> [1] - https://apacheignite.readme.io/docs/sql-queries#off-heap-
> > sql-indexes
> > >>
> > >> [2] - http://apacheignite.gridgain.org/docs/off-heap-memory
> > >>
> > >>
> > >> Thanks,
> > >>
> > >> -Prachi
> > >>
> >
> >
>

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