Re: Still not sexy! (Re: sendfile+zerocopy: fairly sexy (nothing to

[Rick Jones]

> ** I reported that there was also an oddity in throughput values,
> unfortunately since no one (other than me) seems to have access
> to a gige cards in the ZC list, nobody can confirm or disprove
> what i posted. Here again as a reminder:
> 
> Kernel     |  tput  | sender-CPU | receiver-CPU |
> -------------------------------------------------
> 2.4.0-pre3 | 99MB/s |   87%      |  23%         |
> NSF        |        |            |              |
> -------------------------------------------------
> 2.4.0-pre3 | 86MB/s |   100%     |  17%         |
> SF         |        |            |              |
> -------------------------------------------------
> 2.4.0-pre3 | 66.2   |   60%      |  11%         |
> +ZC        | MB/s   |            |              |
> -------------------------------------------------
> 2.4.0-pre3 | 68     |   8%       |  8%          |
> +ZC  SF    | MB/s   |            |              |
> -------------------------------------------------
> 
> Just ignore the CPU readings, focus on throughput. And could someone plese
> post results?

In the spirit of the socratic method :)

Is your gige card based on Alteon?

How does ZC/SG change the nature of the packets presented to the NIC?

How well does the NIC do with that changed nature?

rick jones

sometimes, performance tuning is like squeezing a balloon. one part gets
smaller, but then you start to see the rest of the balloon...

-- 
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