Folks, Bumping up the discussion as it is hitting one of the Ignite users.
The change seams reasonable to me, but it is a breaking change and may affect existing users. Would the community be ok if we change the QueryCursor#getAll method for scan queries? If not, we should expose the keepAll() flag to the public API. пт, 29 июн. 2018 г. в 11:37, Andrey Mashenkov <andrey.mashen...@gmail.com>: > Hi Igniters, > > There is an issue IGNITE-8892 [1] related to OOM during distributed query > execution. > This issue is not limited with ScanQuery usage and looks like affected all > query types. > > The use case is quite simple. 1 server and 1 client. > Client starts scan query with default flags and iterate over cursor. > If whole query result is not fit to memory - JVM will crashed with OOM, > but it is not expected as client takes entries one by one and throw out > them immediately. > Reproducer is attached to the ticket. > > Same query works fine if query starts on server. Seems, we have no > DistributedQueryFuture in that case and all works fine. > > I've found GridCacheDistributedQueryFuture collects all entries and try to > return the collection via onDone(). > This behaviour turn on with a flag 'keepAll' which is true by default. > Iterating over cache via cache.iterator() has no OOM issues as we set > keepAll flag to false. > > Why we have keepAll=true by default as seems noone expects future.get() > will return any data and all queries works through queue in paging mode? > Will it be ok to get rid of 'allCol' and keepAll flag at all? > > I've made a PR and TC looks fine. > Could someone review it, please? > > [1] https://issues.apache.org/jira/browse/IGNITE-8892 > > > -- > Best regards, > Andrey V. Mashenkov >
