Tuning Gigabit

David Gilbert dgilbert at velocet.ca
Sat Jun 28 16:35:55 PDT 2003

>>>>> "Ivan" == Ivan Voras <ivoras at fer.hr> writes:

>> Message: 5 Date: Sat, 28 Jun 2003 13:43:46 +0200 From: "Simon
>> L. Nielsen" <simon at nitro.dk> Subject: Re: Tuning Ggiabit
>> Message-ID: <20030628114342.GB401 at nitro.dk> Content-Type:
>> text/plain; charset="us-ascii"

>>> I've been trying to get my gigabit link to run as fast as
>>> possible, but I have run out of ideas. I've documented (though not
>>> very well) what I have done thus far:
>>> http://craig.afraid.org/a/b?page=computer/gigabit
>>> If there is any more I can do besides what I have already done, I
>>> would love to hear it. Please avoid suggestions that require
>>> spending money.

Ivan> This is probably an obsolete suggestion, but have you increased
Ivan> HZ when you turned on NIC polling? (the web page doesn't mention
Ivan> it)

Unfortunately you may have a motherboard that maxes at 300 megabit.
Our recent testing of Gigabit NICs found more than 75% of the
motherboards we tried unable to pass more than 500 megabit and 25% of
the motherboards wouldn't pass more than 100 megabit.

300 megabit is about where 32bit 33Mhz PCI maxes out.


|David Gilbert, Velocet Communications.       | Two things can only be     |
|Mail:       dgilbert at velocet.net             |  equal if and only if they |
|http://daveg.ca                              |   are precisely opposite.  |

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