The speed in different computer is huge

computer1: ubuntu , cmake 3.16.3
computer2: redhat , cmake 2.8.12

opencv version:
computer2 is better than computer1. but I run a progress:

Mat A(11,11,cv_8uc1);
Mat B(512,512, cv_8uc1)

it is more than 10 times time for computer2.

to characterize these computers, you should state the precise CPU and type and speed of RAM contained in each.

I would strongly suggest using a newer version.

that is a benchmark of nothing but the speed of memory (re)allocations. if you care about speed of any actual algorithms, you should allocate once and then run with that.

cmake is not a compiler. it means nothing
If you want to test speed use perf_test in opencv and post getBuildInformation() for each version

Thank you very much!
I find the reason:
computer1 don’t install TBB, but computer2 installed.

set TBB OFF is OK

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