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Date: Tue, 28 Apr 2015 11:58:14 +0100
From: Bruce Richardson <bruce.richardson@intel.com>
To: Paul Emmerich <emmericp@net.in.tum.de>
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Subject: Re: [dpdk-dev] Performance regression in DPDK 1.8/2.0
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On Tue, Apr 28, 2015 at 12:28:34AM +0200, Paul Emmerich wrote:
> Let me know if you need any additional information.
> I'd also be interested in the configuration that resulted in the 20% speed-
> up that was mentioned in the original mbuf patch
> 
> Paul
> 
The speed-up would be for apps that were doing RX of scattered packets, i.e.
across mbufs. Before 1.8, this was using a scalar function which was rather
slow compared to the fast-path vector function. In 1.8 we introduced a new
vector function which supported scattered packets - it still isn't as fast as
the non-scattered packet RX function, but it was a good improvement over the
older version.

/Bruce