Hi Mapd experts,
I have a confusion about the cpu utilization of mapd. I generated 30G data by TPC-H dbgen tool, and run Q1 sql both in cpu mode and gpu mode, I notice a strange phenomenon:
In cpu mode, the cpu usage rate is about 600% (my machine cpu is Intel E5-2683 with 14 cores, full usage rate should be 2800%)
TIme cost of cpu mode is about 3.2 seconds. And gpu mode is about 0.6 second.
My machine hardware status:
CPU: 2xIntel E5-2683
Video cards:4xGeForce GTX1080, each card has 8G memory installed
My question is, why the utilization of cpu is so low in mapd? Ideally, if all the cpu cores are fully used, the performance of cpu mode should be equals to gpu mode, right?