Re: [PATCH -mm 0/3] sysv ipc: increase msgmnb with the number of cpus

Andrew Morton
2008-07-01T22:18:21Z

On Tue, 24 Jun 2008 11:34:52 +0200
<Solofo.Ramangalahy@bull.net> wrote:

> The size in bytes of a SysV IPC message queue, msgmnb, is too small
> for large machines, but we don't want to bloat small machines.
>
> This series change ("scale") the default value of
> /proc/sys/kernel/msgmnb.

I'm afraid I've lost track of what's happening here. Did we come up
with an alternative to "magical positive-versus-negative number trick"?

Your patch #1 adds and uses recompute_msgmnb() without adding the
declaration to a header file. Your patch #2 does add the
recompute_msgmnb() to a header file, so we have a window in which the
build is broken, which is bad.

recompute_msgmnb() isn't a terribly good globally-visible identifier,
btw. It is nice to add some subsystem identifer as a prefix. There's
little chance of this symbol colliding with anything else, so this is a
minor cosmetic thing in this case.