On 02/26/15 17:34, David Miller wrote: > From: Imre Palik <imrep@xxxxxxxxx> > Date: Thu, 26 Feb 2015 11:19:25 +0100 > >> If you are looking for peculiarities in my setup then here they are: >> I am on 4k pages, and perf is not working :-( >> (I am trying to fix those too, but that is far from being a low hanging fruit.) >> So my guess would be that the packet pipeline doesn't fit in the cache/tlb > > Pure specualtion until you can actually use perf to measure these > things. > > And I don't want to apply patches which were designed based upon > pure speculation. > I did performance measurements in the following way: Removed those pieces of the packet pipeline that I don't necessarily need one-by-one. Then measured their effect on small packet performance. This was the only part that produced considerable effect. The pure speculation was about why the effect is more than 15% increase in packet throughput, although the code path avoided contains way less code than 15% of the packet pipeline. It seems, Felix Fietkau profiled similar changes, and found my guess well founded. Now could anybody explain me what else is wrong with my patch? I run out of ideas what to improve. Thanks Imre
