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Date: Wed, 27 Apr 2016 21:37:04 +0200 (CEST)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Stephen Hemminger <stephen@networkplumber.org>
cc: cake@lists.bufferbloat.net, bloat <bloat@lists.bufferbloat.net>
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Subject: Re: [Cake] [Bloat]   are anyone playing with dpdk and vpp?
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On Wed, 27 Apr 2016, Stephen Hemminger wrote:

> DPDK gets impressive performance on large systems (like 14M packets/sec per
> core), but not convinced on smaller systems.
> Performance depends on having good CPU cache. I get poor performance on

As soon as you can't find information in cache and have to go to RAM to 
get it (and you need it to proceed), you've lost the impressive 
performance.

VPP is all about pre-fetching (tell memory subsystem to go get information 
into cache you probably will need in the not so distant future). It 
actually reminds me of demo programming on C64/Amiga that I was involved 
in in the 80ties. Lots of small optimisations needed to yield these 
results.

So yes, cache is extremely important for VPP.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se