How to control max threads for query execution


#1

Hi,

I am running the open source version of MapD Core without GPU support and try to get some performance number from it.

I want to see the performance number corresponding to different number of query execution threads especially single thread. I looked around but I cannot find where I can configure it. It will be great if anyone can help with this.

Thanks.


#2

If you are running in CPU mode to every thread on Cpu is assigned just one fragment of the table.
The fragments have a default value of 32m of rows, so if your table has 60m of rows mapd will use two core, if has less than 32m just one and so on.
If you want to to take advantage of more cores in Cpu mode, you have to modify that value accordingly at table creation time.

Take look to docs regarding the subject on docs session of website


#3

Thanks a lot! It works!