With the Azul VM (and I believe the G1 collector in Java), the VM is definitely aware of memory pressure as it approaches the maximum limit - then it will increase the concurrent GC activity trying to avoid a potential huge pause if the limit was reached - so throughput is lowered.
I would think the Go GC needs to do this as well in order to limit pause times. > On Sep 12, 2018, at 8:46 AM, Ian Lance Taylor <i...@golang.org> wrote: > > On Tue, Sep 11, 2018 at 11:48 PM, Leigh McCulloch <leigh...@gmail.com> wrote: >> >> Does anyone here know how Go interacts with memory limits inside containers? >> (e.g. Kubernetes, Docker) >> >> Does the Go runtime have similar problems as the Java runtime, in that it >> doesn't know what the container limit is, and only knows what the physical >> limit is for the entire instance? >> >> Or is Go aware of limits placed on the container? >> >> (I've witnessed the Go runtime package say the NumCPU is the total physical >> count when the app has been limited to many less CPUs, so it seems like it >> doesn't have visibility into the CPU limitations.) > > As far as I know, the current implementations of Go don't pay > attention to memory limits at all, whether running inside a container > or not. You may be interested in following > https://golang.org/issue/23044 which could be a first step toward > fixing this. In some sense the core issue is that using memory limits > in a garbage collected language is close to useless if the program > doesn't have a way to react when heap size is nearing the memory > limit. > > On the other hand, on GNU/Linux systems, the CPU count is determined > by calling the sched_getaffinity system call, which as far as I know > is aware of container limits. What leads you to believe otherwise? > > Ian > > -- > 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. > For more options, visit https://groups.google.com/d/optout. -- 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. For more options, visit https://groups.google.com/d/optout.
