On Wed, Jun 7, 2023, 12:33 PM Sven Anderson <s...@redhat.com> wrote: > That’s not only a read/write race, it’s also a write/write race. Every > request to the server creates a new Go routine that might increment > newConns in parallel, so it may get corrupted. Same for lines 39/40. >
The write/write race will happen only if the increment is done from with the new goroutine. If the increment is done after accepting a connection but before starting a new goroutine there is no write/write race, right? But that is not the problem here. Race detector is complaining about a concurrent write after read > You might claim, that for infrastructural reasons, there can be no > concurrent requests to your server, but that would just mean that the race > is not triggered, it’s there nevertheless. > > Caleb Spare <cesp...@gmail.com> schrieb am Mi. 7. Juni 2023 um 01:31: > >> Can someone explain why the following test shows a race between the >> indicated lines? >> >> >> https://github.com/cespare/misc/blob/b2e201dfbe36504c88e521e02bc5d8fbb04a4532/httprace/httprace_test.go#L12-L43 >> >> The race seems to be triggered by the very last line of the test: >> >> get(client1) >> >> If I comment that out, then the race detector doesn't complain. But >> then it seems that a read of a variable which happens before an HTTP >> request which causes a write of the variable ultimately races with the >> original read, which doesn't make sense. >> >> It seems like a false positive (perhaps the race detector doesn't >> understand causality across a TCP connection?), but so far I've never >> seen the race detector have a false positive, so I think I must be >> missing something. >> >> I wrote a slightly simpler test (see TestHTTPRace2 right below in the >> same file) which tries to make the race happen using a regular HTTP >> handler and a single client and the race detector doesn't complain. >> >> Caleb >> >> -- >> 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/CAGeFq%2B%3DZGE5agaLYDgsdYvykbaWwHgjtKJf9q%2B1YJhR26%3DY45Q%40mail.gmail.com >> . >> >> -- > 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/CAFwXxZSzEUtf9M-b0nNYa%2B%3DiaxK%2BmfnJk%3DASKDp1kj2Cx7WqQA%40mail.gmail.com > <https://groups.google.com/d/msgid/golang-nuts/CAFwXxZSzEUtf9M-b0nNYa%2B%3DiaxK%2BmfnJk%3DASKDp1kj2Cx7WqQA%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/CAMV2RqqXFDCFzugXXq-Q0fbTYKqZ1t5KSu06LUtEesRsbja87w%40mail.gmail.com.
