On Sun, Jun 15, 2008 at 11:34:47AM +0200, Jiri Klement wrote:
> > Zero copy will gain you nothing. The server does not starve the CPU but
> >  the disk i/o - so copying around the data comes for free.
> 
> That's correct for throughput but not for latency. Tile processing
> will add to total time needed to get tile because reading and
> processing can't run in parallel. I'm sure cgi will provide tile
> faster (though it might be insignificant compared to total time)

Aeh ? Reading is DMA from disk to memory - Writing to the network is DMA
so - While reading and writing simultaniously the CPU copies other jobs.

And latency wise your CPU can copy 512Mbyte of Ram before the Disk even
started to stream data in. So latency wise the copying is neglectable.

Flo
-- 
Florian Lohoff                  [EMAIL PROTECTED]             +49-171-2280134
        Those who would give up a little freedom to get a little 
          security shall soon have neither - Benjamin Franklin

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