HEADS-UP new statfs structure condidered harmful

Doug White dwhite at gumbysoft.com
Mon Nov 17 09:32:23 PST 2003


On Sat, 15 Nov 2003, Matthew Dillon wrote:

>     I don't understand the question.  All that happens is that functions like
>     fstat() and statfs() become libc functions rather then direct syscalls.
>     The userland program doesn't know the difference, it uses fstat() and
>     statfs() just like it always has.

Well, there's some glue there now, but its pretty slim.   What you
advocate would swap system call numbers for doing structure reloading per
call, which would significantly incrase the cost of the call.
Considering that *BSD system call overhead is pretty bad as is, I don't
think I'd be putting structure recopies into the critical path of a
syscall.

--
Doug White                    |  FreeBSD: The Power to Serve
dwhite at gumbysoft.com          |  www.FreeBSD.org


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