In Go, you can not really limit the maximum number of threads that will be created. The runtime itself will create threads whenever needed for things like blocking CGO calls, garbage collection, network polling, etc. As I understand it, GOMAXPROCS only limits the number of threads that would be spawned to run your actual Go code (i.e. if you create 10 goroutines and you have GOMAXPROCS set to 4, those will all be multiplexed in 4 OS threads at most).
-Bruno On Thu, Feb 1, 2024 at 11:42 AM Steve Roth <st...@rothskeller.net> wrote: > Fair question. In their view, 25 threads per user is a sensible limit. > Their mindset is based around single-threaded PHP. And for that reason > among others, yes, switching providers is definitely something I will > pursue. But that will be a long-term effort. Right now I'm looking for a > short-term solution to get my site back up. > > Thanks, > Steve > > On Thu, Feb 1, 2024 at 8:34 AM Steven Hartland <stevenmhartl...@gmail.com> > wrote: > >> To be honest I would question if its a usable solution if they are >> limiting that low on threads, so is the fix to switch or have the provider >> increase the limit to a sensible number? >> >> On Thu, 1 Feb 2024 at 16:08, Steve Roth <st...@rothskeller.net> wrote: >> >>> Thanks to the people who suggested how to limit the number of apparent >>> cores. Unfortunately, doing that didn't solve the problem. I have the >>> number of cores now limited to two — confirmed by checking runtime.NumCPU() >>> — but the program is still trying to allocate more than 25 threads, and >>> crashing when cgroups won't let it. >>> >>> Surely there must be some way to get a Go program to run successfully in >>> an environment with process limits? Any further suggestions would be >>> greatly appreciated. >>> >>> Regards, >>> Steve >>> >>> >>> On Wed, Jan 31, 2024 at 6:43 PM Steve Roth <st...@rothskeller.net> >>> wrote: >>> >>>> I am running Go code on a shared web hosting server from a major >>>> hosting company. Using cgroups, they limit the number of threads any user >>>> can create to 25. Up until a week ago, they had me running on a server >>>> with 24 cores, and everything worked fine. Now they've moved me to a new >>>> server with 128 cores. The Go runtime thinks it should be able to create >>>> that many threads, and it can't, and all of my Go programs crash with, >>>> "runtime: failed to create new OS thread". >>>> >>>> Setting GOMAXPROCS doesn't help this, since it only controls the number >>>> of active threads, not the total number of threads. The Go runtime still >>>> thinks it can create as many threads as there are cores, and crashes the >>>> program when it's blocked from doing so. >>>> >>>> Is there any way around this? Or is Go just completely unusable in an >>>> environment where the per-user process limit is less than the number of >>>> cores? >>>> >>>> Many thanks, >>>> Steve >>>> >>>> >>>> -- >>> 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/CAAnpqKEzZcFxDkG2Qtzf25hPwkZq2EstbDbYtBz4CtTaBQxqWA%40mail.gmail.com >>> <https://groups.google.com/d/msgid/golang-nuts/CAAnpqKEzZcFxDkG2Qtzf25hPwkZq2EstbDbYtBz4CtTaBQxqWA%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/CAAnpqKH%2BpawFZ2uqC0-wZm2vidngmePhS_%3Dgqfh9iwKPyN%2Bdcg%40mail.gmail.com > <https://groups.google.com/d/msgid/golang-nuts/CAAnpqKH%2BpawFZ2uqC0-wZm2vidngmePhS_%3Dgqfh9iwKPyN%2Bdcg%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/CAEd86TzHNWFf-J9Ez4WpSo1%3DQZprQaJ9j-2JkMx54gBJpH3kMw%40mail.gmail.com.
