On Sun, Jan 31, 2021 at 7:07 PM robert engels <reng...@ix.netcom.com> wrote: > > Not sure the runtime needs it - as all lock usages are known - so the users > in the runtime can ’negotiate’ fairness through other means for a particular > mutex.
Yes. The point of starvation mode in sync.Mutex is to avoid high tail latency for highly contended mutexes, in which one set of goroutines acquiring the mutex can starve a different set of goroutines waiting for the mutex. The runtime does not have highly contended mutexes. When we discover a highly contended mutex in the runtime, we change the code to use a different approach. That is, sync.Mutex has to work reasonably well for any Go program. The runtime.mutex type only has to work well for the runtime package. Ian > On Jan 31, 2021, at 8:56 PM, xie cui <cuiwei...@gmail.com> wrote: > > mutex in sync package and runtime is different, > mutex in runtime package is here, > https://github.com/golang/go/blob/master/src/runtime/lock_futex.go#L46 > i do not see there is a starving mode. > > On Monday, February 1, 2021 at 12:38:08 AM UTC+8 jake...@gmail.com wrote: >> >> What makes you think it does not? Have you looked at Mutex.lockSlow()? I >> have not really worked through the algorithm, but the comments do mention >> starvation mode. >> >> On Sunday, January 31, 2021 at 10:15:23 AM UTC-5 cuiw...@gmail.com wrote: >>> >>> why mutex in runtime do not need starve mode? > > > -- > 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/0cc1fae8-6c22-4e40-9645-425d12bb909dn%40googlegroups.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/E5ADD213-563A-4F32-9467-3F9FC82EDF38%40ix.netcom.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/CAOyqgcWd8map%3DOSRhhibz2nF2G-Rg4nXZLEwt%2BRrGEOjULDXvw%40mail.gmail.com.
