Dear Lorenzo, Here’s a link to an old but still relevant tutorial on benchmarking Go programs
https://dave.cheney.net/2013/06/30/how-to-write-benchmarks-in-go Happy benchmarking On Saturday, February 20, 2021 at 11:19:40 AM UTC-6 TiT8 wrote: > > Thank you Volker. > > I want to say that I was not trying to benchmark the two version of Go > (two weeks ago I had go1.15.8, now 1.16). At the beginning I was trying to > do some linear algebra with Go as a free “alternative of Matlab”, so I > noted the difference between the exe coming from the two versions. > Now I have understand that this is not the way to measure the specific > performance of my issue. I will learn more and also testing. > > Sorry for your time, but thank you very much for your fast help. > Il giorno sabato 20 febbraio 2021 alle 17:31:24 UTC+1 Volker Dobler ha > scritto: > >> (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/aa1f3f18-abcc-4310-8d03-a7102150708en%40googlegroups.com.
