(premature send, sorry) 4. Your matrix multiplication is just a few CPU instructions, it is hard to measure something tiny reliable. So use larger matrixes. 5. You are benchmarking also how fast you can format and output the results to stdout. This might or might not be intentional but probably is just wrong. 6. There is no point in comparing Go 1.15 and Go 1.16 with microbenchmarks which do not properly measure what you think they do. Your code spends far too much time in a lot of things. Come up with a _proper_ benchmark based on testing.B and go test. Make sure this benchmark is stable. Make sure this benchmarks really benchmarks what you are trying to measure. Then redo the benchmarks 10 times and compare them doing proper statistics.
V. On Saturday, 20 February 2021 at 15:48:32 UTC+1 TiT8 wrote: > Hello everyone, > I'm Lorenzo and I'm not a computer scientist, I have used some "Matlab" > and I am new with Go (surprisingly fast, simple and elegant). > > I'm trying to do some basic operation on matrix with the "Gonum" package > using vectorization. I was curious about the speed of development and the > performance (repeat... surprisingly for me!). So I've tried to do some > measures: > > *package main* > > *import (* > * "fmt"* > * "time"* > > * "gonum.org/v1/gonum/mat <http://gonum.org/v1/gonum/mat>"* > *)* > > *func main() {* > * p := mat.NewDense(3, 3, nil)* > * a := mat.NewDense(3, 3, []float64{* > * 1, 2, 3, 1, 2, 3, 1, 2, 3,* > * })* > > * start := time.Now()* > > * p.Mul(a, a) *// element-wise > * fmt.Printf("%v\n", mat.Formatted(p, mat.Prefix(""), mat.Squeeze()))* > * p.Add(a, a) * > * fmt.Printf("%v\n", mat.Formatted(p, mat.Prefix(""), mat.Squeeze()))* > * p.MulElem(a, a)* > * fmt.Printf("%v\n", mat.Formatted(p, mat.Prefix(""), mat.Squeeze()))* > > * fmt.Println(time.Since(start))* > *}* > > > Well... when I run the "go run mat.go" command the result time is about > 150 microseconds, but when I run "go build" and then execute the binary the > result time is about 4 *milli*seconds. This happen when I use go1.16. > > When I use go1.15.8, on the same code, the exe is faster (about 120 > microseconds) then the "go run mat.go" (about 180 microseconds). One order > of magnitude faster than go1.16 exe (and basic Matlab). > > So: > > - am I in error with the code (sorry, it's all new for me)? If yes, > where is my fault? > - if the "benchmark" was correct, why go1.16 build executable is > slower than go1.15.8 exe and "go run" command? > - Is it my machine's fault or Gonum package or what? > - Do you also have these values? > > > My pc: HP ELITEBOOK 8560w Intel(R) Core(TM) i7-2670QM CPU @ 2.20GHz, 2201 > Mhz, 4 Core(s), 8 Logical Processor(s) x64. > I am on the *Windows Subsystem Linux 2. * > > > *Sorry for my English, I hope you understand my issue, thank you for the > attention* > > > > > > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/54fa055b-1c1c-4ccb-a502-96872a00351cn%40googlegroups.com.
