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Subject: Re: Intel P6 vs P7 system call performance
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Ulrich Drepper <drepper@redhat.com>
Cc: Linus Torvalds <torvalds@transmeta.com>,
       Matti Aarnio <matti.aarnio@zmailer.org>,
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On Tue, 2002-12-17 at 18:30, Ulrich Drepper wrote:
> demultiplexing happens in the kernel.  Do we want to do this at
> userlevel?  This would allow almost no-cost determination of those
> syscalls which can be handled at userlevel (getpid, getppid, ...).

getppid changes and so I think has to go to kernel (unless we go around
patching user pages on process exit [ick]). getpid can already be done
by reading it once at startup time and caching the data.


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