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SubjectRe: Gigabit Linux Server Bottlenecks
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>>>>> "Anton" == Anton Ivanov <aivanov@eu.level3.net> writes:

Anton> On 08-Feb-2000 Jonathan Disher wrote:
>>> maddening to the CPU. As I recall, the host must be able to
>>> process around 82,000 packets (read "CPU interrupts") per second
>>> to fill the pipe unidirectionally. Try this in a full duplex
>>> setting with a 2 gig pipe to fill and you (at least) double the
>>> amount of work the CPU needs to accomplish every second.
>> IIRC, gigaether is actually 500mbit ethernet in full duplex mode.

Anton> More complicated:

Anton> In Full Duplex: it is 1 GBit

1 GBit in each direction.

Anton> In Half Duplex: Packets smaller than 640 (or 512, sorry do not
Anton> remember) are padded to this value. So if you transmit 40 byte
Anton> packets in half dupplex you get approx the performance of a 100
Anton> MB in Full Duplex.

Padding is only an issue for Half Duplex, nobody runs GigE at half
duplex.

Jes

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