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Subject: Re: Network stack changes
From: Adrian Chadd <adrian@freebsd.org>
To: Rick Macklem <rmacklem@uoguelph.ca>
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On 13 September 2013 15:43, Rick Macklem <rmacklem@uoguelph.ca> wrote:


> And any time you increase latency, that will have a negative impact on
> NFS performance. NFS RPCs are usually small messages (except Write requests
> and Read replies) and the RTT for these (mostly small, bidirectional)
> messages can have a significant impact on NFS perf.
>

Hi,

the penalties to go to main memory quite a few times each time we process a
frame is expensive. If we can get some better behaviour through batching
leading to more efficient cache usage, it may not actually _have_ a delay.

But, that requires a whole lot of design stars to align. And I'm still knee
deep elsewhere, so I haven't really finished getting up to speed with what
everyone else has done / said about it..



-adrian