Re: [PATCH] Add /proc/pid_generation

On Wed, Nov 21, 2018 at 12:14:44PM -0800, Daniel Colascione wrote:

This change adds a per-pid-namespace 64-bit generation number,
incremented on PID rollover, and exposes it via a new proc file
/proc/pid_generation. By examining this file before and after /proc
enumeration, user code can detect the potential reuse of a PID and
restart the task enumeration process, repeating until it gets a
coherent snapshot.

PID rollover ought to be rare, so in practice, scan repetitions will
be rare.

Then why does it need to be 64-bit?