We report the performance numbersin flops (flop/sec), which is the number offloating point operations(flop)per second (sec). You can find the time required for a routine if you know flop and flop/sec.
For example, the number of floating point operations to compute SGEMM with M=N=K=2048,beta=0.0, alpha=1.0is given as:
2*M*N*K= 2*2048*2048*2048 = 17179869184 flop ~= 17.180 Giga-Flop (GFlop)
Now, if SGEMM runs at 200 GFlop/sec (or GFlops), then the time for SGEMM will be:
17.180 / 200 = 0.0859 secs
Double-precision GEMM (DGEMM) is shown on the performance charts, and as a rule-of-thumb, the single-precision performance is two times of the double-precision performance. Therefore, you can multiply the DGEMM GFlops by two to get an estimate of SGEMM GFlops.