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 >> > >