Re: Linux 2.3.39 has 32bit uid. What about 32bit pid?

[Chris Meadors]

[e-mail] wrote:
> 
> > /proc/sys/kern/max_pid ?
> 
> I do not think that would be meaningful.
> A new distribution comes with recompiled applications.
> People installing things themselves can choose between
> recompiling the applications or configuring with CONFIG_15BIT_PID.
> If the default is to use 31 bits instead of 15 bits, then I cannot
> see any need for dynamically adjusting max_pid.
> 
> (And I would prefer things to be right by default, not that we
> all have to add stuff to our rc scripts with
>         echo 2147483647 > /proc/sys/kern/max_pid
> or so. Before you know it this will grow into an entire industry,
> with scripts trying to determine whether some old ipc using stuff
> still exists, and to use an appropriate echo.)

Another thing to consider with a dynamic max_pid.  What happens to
processes running in the 31 bit pid space (above 32k) when you cut it
back down to 15 bit?