Hi all, I have two services deployed on Google cloud infrastructure; Service 1 runs on Compute Engine and Service 2 on Cloud Run and I'd like to log their memory usage via the `ekg-core` library (https://hackage.haskell.org/package/ekg-core-0.1.1.7/docs/System-Metrics.htm...) (which is just a thin wrapper around GHC.Stats ). The logging bracket is basically this : mems <- newStore registerGcMetrics mems void $ concurrently io (loop mems) where loop ms = do m <- sampleAll ms ... (lookup the gauges from m and log their values) threadDelay dt loop ms I'm very puzzled by this: both rts.gc.current_bytes_used and rts.gc.max_bytes_used gauges return constant 0 in the case of Service 2 (the Cloud Run one), even though I'm using the same sampling/logging functionality and build options for both services. This is about where my knowledge ends; could this behaviour be due to the Google Cloud Run hypervisor ("gRun") implementing certain syscalls in a non-standard way (gRun syscall guide : https://gvisor.dev/docs/user_guide/compatibility/linux/amd64/) ? Thank you for any pointers to guides/manuals/computer wisdom. Details : Both are built with these options : -optl-pthread -optc-Os -threaded -rtsopts -with-rtsopts=-N -with-rtsopts=-T the only difference is that Service 2 has an additional flag -with-rtsopts=-M2G since Cloud Run services must work with 2 GB of memory at most. The container OS in both cases is Debian 10.4 ("Buster").