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

[Khimenko Victor]

In <[e-mail]> Alan Cox ([e-mail]) wrote:
>> Thus, if we change get_pid() so as to use pids larger than 32000
>> we need CONFIG_15BIT_PID (default=n) so that people who cannot or
>> do not want to recompile their ipc using stuff can use a new kernel.

> /proc/sys/kern/max_pid ?

Perhaps.

>> (Only very few programs are affected. Making new rpms available
>> for people upgrading to 2.4 would suffice.)

> Then I think it is worth while, shared cluster folks have been asking about
> stuff like node <<8 | pid for a while, and 16bit pid_t is going to be too
> small the way big PC kit is going

That's where 64bit pid_t with only 32bit really used will be ideal :-) On
32bit platforms 64bit pid_t is to expensive, though...

>> Aha, so that was obstacle 1. Obstacle 2 is the inode numbering the kernel
>> uses internally for /proc. That would have to change.

> True