Hello Fawze,

Disabling this, per se, is not an option, but an equally simple workaround
is using MEM_LIMIT.

The estimated stats are often very far from actual memory usage and
shouldn't be relied on - a best practice is to set MEM_LIMIT as a query
option (preferably have a default value set for each pool). Having that set
will cause Impala to ignore the estimates and rely on this limit for
admission control purposes. This works decently for well-understood
workloads (ie. where the memory consumption is known to fit within certain
limits). For ad-hoc workloads, if the query can't be executed within the
default limit of the pool, you can override the limit on a per-query basis
(just issue 'set MEM_LIMIT=...' before running the query).

HTH

On 16 June 2018 at 13:31, Fawze Abujaber <[email protected]> wrote:

> Hi Community ,
>
> In the last impala versions, impala is estimating the memory required for
> the query, and in case the estimated memory required beyonds the configured
> memory or  the configured memory per pool, impala is not submitting this
> query, taking the fact that many times and specially running query on
> tables without stats there is a huge difference between the estimated and
> the actual memory used, the estimated can be 31 GB per node and the actual
> use is 1 or 2 GB, that’s mean to submit a query I need at least 1.5 T
> memory configured which I see it too much.
>
> I’m curios to know if there is an option making this to configuration ( Un
> submitting query if we he estimated memory required beyond the configured
> memory) as an optional choice.
>
> Such issue can block using impala dynamic resource pools.
> --
> Take Care
> Fawze Abujaber
>

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