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A comment on Using Flat Files So Elections Don’t Break Your Server. Parent comment

Re:Using Flat Files So Elections Don’t Break Your Server by sambeau on Tuesday December 21, 2010 @12:08PM (#2028419)
I was under the (possibly mistaken) impression that Direct Memory Access (DMA) hardware could move data straight from the Disk Cache to the Network card without touching the CPU Caches at all.
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Re:Using Flat Files So Elections Don’t Break Your Server by dedward on Wednesday December 22, 2010 @10:00PM (#2033360)
True - DMA can do that - but then you'd have to have something managing the network stack - the kernel manages tcp/ip.

From the man page:

"sendfile() copies data between one file descriptor and another. Because this copying is done within the kernel, sendfile() is more efficient than the combination of read(2) and write(2), which would require transferring data to and from user space."

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