On Mon, Apr 23, 2018 at 11:54:57AM +0300, Tariq Toukan wrote: > Hi, > > I ran my tests with your patches. > Initial BW numbers are significantly higher than I documented back then in > this mail-thread. > For example, in driver #2 (see original mail thread), with 6 rings, I now > get 92Gbps (slightly less than linerate) in comparison to 64Gbps back then. > > However, there were many kernel changes since then, I need to isolate your > changes. I am not sure I can finish this today, but I will surely get to it > next week after I'm back from vacation. > > Still, when I increase the scale (more rings, i.e. more cpus), I see that > queued_spin_lock_slowpath gets to 60%+ cpu. Still high, but lower than it > used to be. I wonder if it is on allocation path or free path? Also, increasing PCP size through vm.percpu_pagelist_fraction would still help with my patches since it can avoid touching even more cache lines on allocation path with a higher PCP->batch(which has an upper limit of 96 though at the moment). > > This should be root solved by the (orthogonal) changes planned in network > subsystem, which will change the SKB allocation/free scheme so that SKBs are > released on the originating cpu.
