Re: [PATCH] processes with shared vm

[Dave McCracken <dmccr@us.ibm.com>]

--On Friday, August 17, 2001 10:46:59 +0200 Terje Eggestad 
<terje.eggestad@scali.no> wrote:

> hought of all that, yes ps will have O(n^2) BUT ONLY FOR CLONED PROCS.
> How many cloned procs do you usually have????
>
> Even if I agree that there should be a linked list of all the cloned
> procs, it means major changes to the data structs in the kernel.
>
> With the number of threaded programs out there, this is "good enough".

There is a simpler way to do this.  All tasks belong to a thread group, and 
while thread groups are connected via a different clone flag 
(CLONE_THREAD), in practice CLONE_THREAD and CLONE_VM are generally used 
together.  It would be trivial to add TGID to the information in /proc, 
then assume all tasks with the same TGID have the same VM as well.  It 
would be just one more line in the /proc output and not require any 
additional overhead.

Dave McCracken

======================================================================
Dave McCracken          IBM Linux Base Kernel Team      1-512-838-3059
dmccr@us.ibm.com                                        T/L   678-3059