Re: [RFC -mm 0/6] sysv ipc: scale msgmnb with the number of cpus

Solofo.Ramangalahy
2008-06-23T13:14:54Z

Hi Manfred,

This part is more difficult to answer than the other one:
> The whole configuration can be done from user space, thus I assumed that
> a sysctl.conf value [...] could do the job

Yes, while this is (still) possible, this can become cumbersome with
namespaces, hotplug, ...

> (or in the worst case: a dbus/hal daemon that
> updates /proc/sys/kernel/msgnmb) [...]

This would probably mean one daemon per ipc namespace.
The patches seems lighter.

There has been related discussions regarding kernel
space vs. userspace approach in the threads:
. "Change in default vm_dirty_ratio"
http://lkml.org/lkml/2007/6/18/471
. "[RFC][PATCH 0/6] Automatic kernel tunables (AKT)"
http://lkml.org/lkml/2007/1/16/16
(and probably others)

So it seems there is no consensus in doing it either way: kernel or
user space.

Humm... now this make me think that you did not change the MSGMNB
value when you changed MSGMNI and MSGMAX.
Maybe that was on purpose?

--
solofo