Chris C wrote:

> Nieminen Mika <war### [at] cctutfi> wrote:
>
> >  I wonder how is this done. Unless unix overclocks the cpu without telling
> >you... :)
>
> It's quite obvious, if you think about it. Any application on a modern OS must
> share the CPU with - at the very least - the OS, if not other applications. In
> addition, the application will typically depend on the OS for various services.
>
> The more efficient the OS is in keeping out of the application's way, and the
> more efficiently coded the services it offers are, the more time the
> application has to do its work.
>
> Windows 95/98 are woeful in that respect - they still have chunks of 16-bit
> code in them, which causes a contect switch every time they're called from
> 32-bit mode.
>
> Windows NT - while a true 32/64-bit OS - still has more overhead than modern
> unixes.
>
> So, a good Unix such as FreeBSD or Linux will typically run (compiler
> optimisations not considered) the same code on the same hardware faster than
> Windows.
>
> -- Chris

And another factor is how memory and drive space are handled. NTFS was originally
hyped as not ever needing defragmentation. NT5 is going to include a third-party
developed defragmenter. Hmmm. Convey anything about their file system design?

Also, the swapping in NT is horrible. Well, OK maybe not that bad, but it can be a
factor. Especially with a program like PovRay.

And Win9X is another big problem. Any 16-bit process executing will block all
32-bit processes until it complets. In windows multimedia development, I've had
simple test cases where a timer callback for MIDI playing could get a 2100ms
latency! 2.1 seconds of non-callback just because I happened to be accessing
ethernet at the time. Ouch!

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