DragonflyBSD fast syscall support and x86 improvements

Attilio Rao attilio at freebsd.org
Thu Jun 29 07:54:36 PDT 2006

2006/6/28, David Xu <davidxu at xxxxxxxxxxx>:
I have a complete patch for FreeBSD to support sysenter/sysexit,
in fact, it is running on my machine for months, but I must say
it is useless, I saw no performance improvement in real world,
yes, in benchmark world, you can measure the improvement by doing
getuid() syscall, and you found it is a lot faster, but in
real world, application is more complex, and doing heavy work
How much it is faster in percentage?
The fact that in real world it loosed the hypotetical improvement can
be given by a couple of different factors:
- wrong benchmarks in the 'test' case or in 'real' case
- not counting important aspects in implementation that slows your code too.
- etc.
I will review it ASAP, thanks for this interesting pointer.


Peace can only be achieved by understanding - A. Einstein

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