On Fri, 15 Nov 2019 at 21:52, Willem de Bruijn <willemdebruijn.kernel@xxxxxxxxx> wrote: > > On Thu, Nov 14, 2019 at 3:47 AM Naresh Kamboju > This appears to have been flaky from the start, particularly on qemu_arm. This is because of emulating 2 CPU. I am gonna change this to emulate 4 CPU for qemu_arm. > > Looking at a few runs.. > > failing runs exceeds bounds: > https://lkft.validation.linaro.org/scheduler/job/1006586 ... > delay29722: expected20000_(us) # > # ./so_txtime exceeds variance (2000 us) > " > These are easy to suppress, by just increasing cfg_variance_us and > optionally also increasing the delivery time scale. Alright ! The variance is 2000. static int cfg_variance_us = 2000 > Naresh, when you mention "multiple boards" are there specific > microarchitectural details of the hosts that I should take into > account aside from the qemu-arm virtualized environment itself? The easy to reproduce way is running 32-bit kernel and rootfs on x86_64 machine. arm32 bit beagleboard x15 device. qemu-arm command line, qemu-system-aarch64 -cpu host,aarch64=off -machine virt-2.10,accel=kvm -nographic -net nic,model=virtio,macaddr=BA:DD:AD:CC:09:02 -net tap -m 2048 -monitor none -kernel zImage --append "console=ttyAMA0 root=/dev/vda rw" -drive format=raw,file=rpb-console-image-lkft-am57xx-evm-20191112073604-644.rootfs.ext4,if=virtio -m 4096 -smp 2 -nographic > Very nice dashboard, btw! Thanks for your valuable feedback. Great to hear this :-) - Naresh
