Alan Cox wrote:
> > so there's still single copy for write() of a mmap()ed page?
>
> An mmap page will go direct to disk.
Looking at the 2.4.4 code, mmap() of file followed by write() to socket
will copy the data once.
I could be mistaken (only glanced at the code quickly) but I base that
on the only call to ->sendpage being through sendfile.
So yes, there's a single copy overhead for mmap()+write().
-- Jamie
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This archive was generated by hypermail 2b29 : Tue May 15 2001 - 21:00:13 EST