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From Alexei Scherbakov <alexey.scherbak...@gmail.com>
Subject Re: IGNITE-2795
Date Thu, 07 Jul 2016 15:51:55 GMT
I've updated the fix.

Currently all the copying is performed inside query iterators only if
needed.

2016-07-07 14:38 GMT+03:00 Alexei Scherbakov <alexey.scherbakoff@gmail.com>:

> Denis,
>
> I think the current state of fix for SQL queries is consistent with the
> highlighted topics, except
>
> - server node mustn’t create a copy if a result set will be transferred to
> a remote node;
>
> I afraid it would be difficult to implement without interfering with
> current implementation too much.
> Will look at this more thoughtfully.
>
> Anyway, it would be useful for me if someone will review the current state
> and provide suggestions.
>
>
> 2016-07-07 13:32 GMT+03:00 Denis Magda <dmagda@gridgain.com>:
>
>> I would say that, yes, we should make copyOnRead flag consistent across
>> all cache ‘get’ like operations. However we need to make sure that the copy
>> is not created in the following cases
>>
>> - server node mustn’t create a copy if a result set will be transferred
>> to a remote node;
>> - client node or other remote node mustn’t create a copy after it
>> receives the result set from the other node.
>>
>> All this means that the copy has to be created if:
>> - node (server) executes local queries or iterates over local data set;
>> - client does the same executing queries or iterating over its local
>> cache.
>> - in my understanding, in OFF_HEAP mode in doesn’t make sense to make a
>> copy in any case since Java heap already has a copy of data from off heap.
>> However this part must be clarified by someone else from the community.
>>
>> Would you mind covering this scenarios in the tests and implementation?
>>
>> Igniters, other thoughts on this?
>>
>> —
>> Denis
>>
>> > On Jul 7, 2016, at 12:18 PM, Alexei Scherbakov <
>> alexey.scherbakoff@gmail.com> wrote:
>> >
>> > Igniters,
>> >
>> > I implemented a fix for copy-on-read semantics for cache objects
>> returned
>> > from SQL queries and need a review.
>> >
>> > See the issue <https://issues.apache.org/jira/browse/IGNITE-2795>for
>> > details on PR.
>> >
>> > While developing a fix I also noticed the same bug in local cache
>> > iterators.
>> >
>> > To make a behavior of copyOnRead consistent across all cache
>> operations, I
>> > think we should fix it as well.
>> >
>> > Thoughts?
>> >
>> > --
>> >
>> > Best regards,
>> > Alexei Scherbakov
>>
>>
>
>
> --
>
> Best regards,
> Alexei Scherbakov
>



-- 

Best regards,
Alexei Scherbakov

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