Re: [ACPI] ACPI mentioned on lwn.net/kernel

[Jamie Lokier <lk@tantalophile.demon.co.uk>]

Dan Maas wrote:
> This may be true for environments where people mostly run a handful of
> monolithic applications (*ahem* windows) but look at typical Linuxy things
> like:
> 
> make (compiler, assembler, linker processes...)
> forking servers (Apache 1.x...)
> *./configure scripts* (a big one!!!)
> etc...
> 
> Startup cost is likely to be a big factor here...

Btw, a little story about startup times and Linux.

I once wrote a Perl script that needed to know the current directory.
It did:

   use POSIX 'getcwd'
   getcwd(...)

After a few months, I was annoyed by the slowness of this script
(compared with other scripts) and decided to try speeding it up.  It
turns out that the above two lines took about 0.25 of a second, and that
was the dominant running time of the script.

I replaced getcwd() with `/bin/pwd`.  Lo!  It took about 0.0075 second.

Says very good things about Linux' fork, exec and mmap times, and about
Glibc's dynamic loading time, I think.

-- Jamie