Re: /proc guidelines and sysctl

[Martin Dalecki]

"Albert D. Cahalan" wrote:
> 
> Martin Dalecki writes:
> > [e-mail] wrote:
> 
> >> Actually the bloat/mess has to be somewhere. Either in userspace
> >> trying to make sense/stay in sync with the kernel structures,
> >> or in the kernel where it has the structures. Obviously everything
> >> shouldn't go in /proc, but there things that are simplier either
> >> in the kernel or in user space.
> 
> I rewrote ps. Properties of a good solution might be:
> 
> 1. single system call returns an array
> 2. all values are 64-bit (larger values can be split)
> 3. binary data
> 4. reasonable choice over what data is returned
> 
> Of course, ps must use the Linux kernel 2.2.x /proc for a while.

The process status relate sutff there is no problem for me.
What makes me shudded mostly are all those other not well outtought
little ugly animals which reside there. Bascially not just animals but
gangs
of them... It may be well worth to give back life to the sysinfo call to
solve
the problem of getting at free/vmstat info.
 
> >> In some of the embedded projects we do space is a big issue,
> >> and /proc actually allows us to save space by not putting a lot
> >> of tools (like ps) in the precious flash.
> ...
> > Or just do size /bin/ps on a free BSD box and compare the reslut's
> > with the same on linux (assuming you didn't compile the procps lib
> > as shared...) Why do you think we have currently make bzlilo
> > instead of make zlilo now?
> 
> You can use minimal.c to get a library-free 8 kB ps.
> http://www.cs.uml.edu/~acahalan/linux/procps-991122.tar.gz
> 
> > The first race in /proc I can think of is for example the simple
> > fact that ps doesn't really get a true snap of the systems state,
> > there are chances that it will change under the feets of it...
> 
> It is not reasonable to get such a snapshot. If every process has
> a full comand line and you have 32767 processes, you need over 4 GB.
> Actually, that means ps is automatically broken on 32-bit systems.

--
	Marcin Dalecki