Hi Jeszy,

Thanks for your response, Indeed this is what i was thinking about but, I
have  Default Query Memory Limit and Max memory set per pool which i think
should be enough to cover this, shouldnot it?  or i should pass the
mem_limit in the default query options?

On Sun, Jun 17, 2018 at 8:36 PM, Jeszy <[email protected]> wrote:

> 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
>>
>
>


-- 
Take Care
Fawze Abujaber

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