Re: How to know HZ from userspace?

[Harald Welte]

On Wed, Jun 06, 2001 at 08:59:51PM +0200, Tomas Telensky wrote:
> > On Wed, Jun 06, 2001 at 08:09:33PM +0200, Tomas Telensky wrote:
> > > > Hi!
> > > > 
> > > > Is there any way to read out the compile-time HZ value of the kernel?
> > > 
> > > Why simply #include <asm/param.h>?
> > 
> > because the include file doesn't say anything about the HZ value of 
> > the currently running kernel, but only about some kernel source somewhere
> > on your harddrive?
> 
> This _SHOULD_ correspond on each linux instalation. But if you would
> distribute a binary to other people it's a problem.

I my initial mail I wrote that I'm talking about user-mode-linux. So for
example you compile a program, copy it into your user-mode-linux filesystem,
and it won't work anymore. (recompiling is also not an option, who has a 
kernel source installed inside his user-mode-linux root filesystem).

and what happens if you recompile your kernel with a different HZ (because
of tc's TBF or something)... then you would have to recompile your userspace
application afterwards?

nah. That's not a solution.

I'd say:

- Either change all sysctl variables to be HZ-independent, or
- Create a sane way to read HZ from the running kernel.

Everything else is broken, from my point of view.

> 	Tomas

-- 
Live long and prosper
- Harald Welte / [e-mail]               http://www.gnumonks.org/
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