Setting the large and small queue to 1 would'nt do it because the queues could be operating simultaneously, says Dev. To serialize all incoming queries, set the small queue at 0 and the exec.queue.threshold at 0.
Kristine Hahn Sr. Technical Writer 415-497-8107 @krishahn On Wed, May 13, 2015 at 2:51 PM, Richard Shaw <rs...@maprtech.com> wrote: > Thank you Kristine > > Please can you confirm the following would have the desired effect of > completely serialising all incoming queries? > > ALTER SYSTEM SET `exec.queue.enable`=true; > ALTER SYSTEM SET `exec.queue.small`=1; > ALTER SYSTEM SET `exec.queue.large`=1; > > > Kind Regards, > Richard > > > On 30 April 2015 at 14:46, Kristine Hahn <kh...@maprtech.com> wrote: > >> Set options in sys.options to enable and manage query queuing, which is >> turned off by default. There are two types of queues: large and small. You >> configure a maximum number of queries that each queue allows by configuring >> the following options in the sys.options table: >> >> - exec.queue.large >> - exec.queue.small >> >> Example Configuration >> >> For example, you configure the queue reserved for large queries to hold a >> 5-query maximum. You configure the queue reserved for small queue to hold >> 20 queries. Users start to run queries, and Drill receives the following >> query requests in this order: >> >> - Query A (blue): 1 billion records, Drill estimates 10 million rows >> will be processed >> - Query B (red): 2 billion records, Drill estimates 20 million rows >> will be processed >> - Query C: 1 billion records >> - Query D: 100 records >> >> The exec.queue.threshold default is 30 million, which is the estimated >> rows to be processed by the query. Queries A and B are queued in the large >> queue. The estimated rows to be processed reaches the 30 million threshold, >> filling the queue to capacity. The query C request arrives and goes on the >> wait list, and then query D arrives. Query D is queued immediately in the >> small queue because of its small size, as shown in the following diagram: >> >> [image: Inline image 1] >> >> The Drill queuing configuration in this example tends to give many users >> running small queries a rapid response. Users running a large query might >> experience some delay until an earlier-received large query returns and the >> large queue is available to continue processing large queries. >> >> Kristine Hahn >> Sr. Technical Writer >> 415-497-8107 @krishahn >> >> >> On Thu, Apr 30, 2015 at 12:04 AM, Richard Shaw <rs...@maprtech.com> >> wrote: >> >>> I'd like to better understand queuing, if it's in fact possible to >>> serialise incoming queries, especially where I have a very small Drill >>> installation with limited resources. >>> >>> Thank you >>> >>> Kind Regards, >>> Richard >>> >> >> >
