latency (was: RE: cooling door)

Sun Mar 30 01:30:50 UTC 2008

On Sat, 29 Mar 2008, Frank Coluccio wrote:

> Please clarify. To which network element are you referring in connection with
> extended lookup times? Is it the collapsed optical backbone switch, or the
> upstream L3 element, or perhaps both?

I am talking about the matter that the following topology:

server - 5 meter UTP - switch - 20 meter fiber - switch - 20 meter 
fiber - switch - 5 meter UTP - server

has worse NFS performance than:

server - 25 meter UTP - switch - 25 meter UTP - server

Imagine bringing this into metro with 1-2ms delay instead of 0.1-0.5ms.

This is one of the issues that the server/storage people have to deal 
with.

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