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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Sergey Babkin <babkin@verizon.net>
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Subject: Re: is RTL8139 THAT bad?
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>>
>> But - this computer can do memcpy at 80MB/s, so at 3.5MB/s it should be 5%
>> CPU for memcpy, and one interrupt per one packet (2500 packets/s).
>>
>> Is something more that make it consume >50% CPU?
>
> Accessing the on-card memory through PCI is guaranteed to be
> slower than the main memory, and depending on the particular
> card it may be much slower.

as comment say - this card do DMA to main memory then computer must copy.

so PCI speed needs just to be faster than 100Mbit/s, certainly is