N1ql max parallelism

Hello,

  1. Is there a way to find what was the parallelism in use for a completed n1ql (may be from system keyspace)?

  2. Documentation states that max parallelism can be specified for a request (n1ql). Can max_parallelism be specified in Query Workbench for a n1ql?

Thanks

If you did not change it is default 1.

In QWB top right corner there is preferences. You can set there.

https://docs.couchbase.com/server/current/tools/query-workbench.html#query-preferences

Thank you.

I have a single node cluster running Data, Index & Query services. It has a total of 24 vCPUs and there is absolutely nothing running on the cluster, in other words resources are free.

On the CBQ prompt, I set max parallelism to 4 and executed a query.

  1. Since it is a single node cluster (but it does have 24 vCPUs), will it actually use a parallelism of 4 ?
  2. I did not see any visible difference in the execution time. Hence wanted to know if there is a way to check what was the actual parallelism in effect for that execution?

Regards

CE query service comes with limited concurrency and parallelism and supports a maximum of 4 cores per node

https://docs.couchbase.com/server/current/introduction/editions.html

Hi, Yes. Am aware about CE and its limitation of max 4 cores. But we are not running CE. Its EE.

Given that its EE, can you help understand on the 2 queries. Thanks!

What all the queries. Please post them

Sure. Re-posting:

I have a single node cluster running Data, Index & Query services. It has a total of 24 vCPUs and there is absolutely nothing running on the cluster, in other words resources are free.

On the CBQ prompt, I set max parallelism to 4 and executed a query.

  1. Since it is a single node cluster (but it does have 24 vCPUs), will it actually use a parallelism of 4 ?
  2. I did not see any visible difference in the execution time. Hence wanted to know if there is a way to check what was the actual parallelism in effect for that execution?

Thanks

max_parallelism is used part of query where it can execute in parallel. It all depends on query.

Cluster level/node level might limited 1 checkout queryMaxParallelism in following link
https://docs.couchbase.com/server/current/settings/query-settings.html

If you set profile timings, it should have copies field in parallel operator