Reply
New Contributor
Posts: 2
Registered: ‎02-20-2014

Impala queries defaults to a max 20 queries and not configurable

[ Edited ]

Hi,

  I recently upgraded to CDH 5.1.0. Since then I am not able to see more than 20 executing queries on the queries tab of Impala service. 

I followed : 

http://www.cloudera.com/content/cloudera-content/cloudera-docs/CDH5/latest/Impala/Installing-and-Usi...

And

http://www.cloudera.com/content/cloudera-content/cloudera-docs/CDH5/latest/Impala/Installing-and-Usi...

 

I had setup Dynamic resource pool also with default Impala configurations as :

Max running queries: 100

Max memory: 540000MB

Max Queried Queries: 500.

 

I had even added safety value entries cluster wise also as:

-default_pool_max_queued=100
-default_pool_mem_limit=540G
-queue_wait_timeout_ms=36000000
-llama_max_request_attempts=100
--default_pool_max_requests=100

 

First issue is that, the earlier queries are not getting cancelled even after my reporting dashboard has created the reports/charts and secondly the configurations which I made as explained above doesnt look like getting into effect even after restarting service and deploying client configurations.

 

Please suggest if I am missing anything or need to do something else.

 

Thanks,

Guru

 

Explorer
Posts: 12
Registered: ‎05-03-2017

Re: Impala queries defaults to a max 20 queries and not configurable

I know this an old post but I have had a similar problem where I changed max running queries to 25 under 'Impala admission control' but then a couple of days later got an error in HUE(impala) saying max queries of 15 was exceeded.... what is up with that ? it seems the setting of 25 has not taken effect.
Cloudera Employee
Posts: 385
Registered: ‎07-29-2015

Re: Impala queries defaults to a max 20 queries and not configurable

@Daggersis it possible that you didn't refresh the admission control pool configurations after changing them?

 

Explorer
Posts: 12
Registered: ‎05-03-2017

Re: Impala queries defaults to a max 20 queries and not configurable

I don't think so. There is nothing to tell me otherwise. When I go into admission control it is set to 25. Is there a way to double check ?
Cloudera Employee
Posts: 385
Registered: ‎07-29-2015

Re: Impala queries defaults to a max 20 queries and not configurable

There's a big "Refresh Dynamic Resource Pools" button in the bottom-left of the "Impala Admission Control" screen when the configs are stale.
Explorer
Posts: 12
Registered: ‎05-03-2017

Re: Impala queries defaults to a max 20 queries and not configurable

[ Edited ]
Yes and that is not there. Also this message in the log of impala indicates it is set(I think) impalad.pxlbig04.nz.thenational.com.impala.log.INFO.20190117-104024.29754:I0117 10:43:37.781446 34548 admission-controller.cc:510] Schedule for id=d34a40c71691c6d7:a345018b00000000 in pool_name=root.default cluster_mem_needed=90.00 GB PoolConfig: max_requests=25 max_queued=15 max_mem=1024.00 GB So the question is how come I get this error in HUE(impala) sometimes: Rejected query from pool root.default: queue full, limit=15, num_queued=16 [‎14/‎01/‎2019 1:23 p.m.] Oh !!!! I think I have answered my own question. There must have been 25 already running so the limit I have hit must be max_queued... yes ?
Highlighted
Cloudera Employee
Posts: 385
Registered: ‎07-29-2015

Re: Impala queries defaults to a max 20 queries and not configurable

Yeah looks like that is it! If the queue has space the query would just get
queued instead.
Announcements