Hi, another thing to keep in mind is that `GOMAXPROCS=1` does not actually make your program single-threaded:
The GOMAXPROCS variable limits the number of operating system threads that > can execute user-level Go code simultaneously. There is no limit to the > number of threads that can be blocked in system calls on behalf of Go code; > those do not count against the GOMAXPROCS limit. (from https://golang.org/pkg/runtime/#hdr-Environment_Variables) So, as long as your program uses blocking syscalls (the overwhelming majority of Go programs do), the runtime will still spawn multiple threads. So if you have, say, multiple Goroutines that read from files, the order in which the `Read` calls return is probably non-deterministic. FWIW, the playground used to be completely deterministic. Recently it started using gVisor though and I don't know how deterministic this new runtime is. But with a sufficiently old Go version you can get deterministic execution by compiling to NaCl. On Mon, Nov 2, 2020 at 6:52 PM Kurtis Rader <kra...@skepticism.us> wrote: > On Sun, Nov 1, 2020 at 9:15 PM Ting Yuan <yuant...@ict.ac.cn> wrote: > >> I find it is tricky to debug a concurrency Go program in multi-core >> systems, so I wonder if there is a way to make the program run in >> deterministically. Can I assume a program with GOMAXPROCS(1) can be >> deterministically >> executed ? >> > > In addition to Harald's answer I'll point out you should be running your > unit tests with race detection enabled. If you don't have good test > coverage you may want to enable race detection in your binary. See > https://golang.org/doc/articles/race_detector.html > > -- > Kurtis Rader > Caretaker of the exceptional canines Junior and Hank > > -- > 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/CABx2%3DD-khBVjC6Kg3NRi6DLYxHsX9wSX3u5NT_tgeNP-CK3bcA%40mail.gmail.com > <https://groups.google.com/d/msgid/golang-nuts/CABx2%3DD-khBVjC6Kg3NRi6DLYxHsX9wSX3u5NT_tgeNP-CK3bcA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- 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/CAEkBMfH2bqKOgXa%2Bv-hO-TDO0tR1Jnw8bKESVOgq4sJ6Mvq6Eg%40mail.gmail.com.
