Re: zero copy issue while receiving the data (counter part of sendfil e)

[John W. Linville]

On Wed, Dec 22, 2004 at 04:50:05PM +0100, Martijn van Oosterhout wrote:

> Generally, reading from memory takes time because the CPU has to wait,
> writing is free since it can be deferred in the cache (in theory
> indefinitly) until there's free cycle.

I'm not sure I'd call that "free" -- executing the instructions for
the write has a non-zero cost.

Still, it is significantly cheaper than the read...

John
-- 
John W. Linville
linville@xxxxxxxxxxxxx
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