I am sorry, I was unclear. The app uses very little ram but the provisioned available memory is 512 MB.
I will try to experiment with GC toggles as you suggest and report back. Thx! On Sat, Dec 2, 2017, 22:18 rlh via golang-nuts <golang-nuts@googlegroups.com> wrote: > Hard telling what it going on. 35MB, even for 1 CPU, seems very small. > Most modern system provision more than 1GB per HW thread though I've seen > some provision as little as 512MB. GOGC (SetGCPercent) can be adjust so > that the application uses more of the available RAM. Running with > GODEBUG=gctrace=1 will give you a sense of the GC's view of the application. > > In any case these kinds of numbers, running on a real systems, and > duplicatable on tip are worth filing an issue. > > On Saturday, December 2, 2017 at 3:02:30 AM UTC-5, Henrik Johansson wrote: >> >> Hi, >> >> I am befuddled by GC SW times on several seconds (seen 20s once) in the >> metrics page for our app. There are several things that are strange but >> perhaps I am misreading it. The same metrics page reports Max Total 35 MB >> out of which 1 MB s swap the rest RSS. The response times on the service is >> has 99% ~400 ms which is not good but 95% is ~120 ms usually. >> The app reloads an in memory cache as needed using atomic,Value as a >> holder and the size is no more than a few thousand at any given time. >> Basically a map with pointers to simple structs and lists with pointers >> to the same structs to allow for some simple access scenarios. >> >> Now I haven't profiled the app yet but even in a very pathologial case it >> seems as though the GC would be able to keep up easily with such little >> amount of memory being used. Granted this is a Standard 1x dyno but even so >> once the machiine is stopped the GC should be able to complete it's work in >> a very short time given the low used memory. >> >> Has anyone seen this as well? Could the Go metrics on Heroku simply >> report erroneously? Perhaps a couple of orders of magnitide? >> >> Cheers, >> >> -- > 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.
