On Tue, May 21, 2019 at 12:28:48PM +0200, Rafał Miłecki wrote: > Hi, > > I work on home routers based on Broadcom's Northstar SoCs. Those devices > have ARM Cortex-A9 and most of them are dual-core. > > As for home routers, my main concern is network performance. That CPU > isn't powerful enough to handle gigabit traffic so all kind of > optimizations do matter. I noticed some unexpected changes in NAT > performance when switching between kernels. > > My hardware is BCM47094 SoC (dual core ARM) with integrated network > controller and external BCM53012 switch. Guessing, I'd say it's to do with the placement of code wrt cachelines. You could try aligning some of the cache flushing code to a cache line and see what effect that has. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up