[systemd-devel] Improving module loading

[Greg KH]

On Sat, Dec 20, 2014 at 10:45:34AM +0000, Hoyer, Marko (ADITG/SW2) wrote:
> Hi,
> 
> > -----Original Message-----
> > From: systemd-devel [mailto:systemd-devel-
> > bounces at lists.freedesktop.org] On Behalf Of Umut Tezduyar Lindskog
> > Sent: Tuesday, December 16, 2014 4:55 PM
> > To: systemd-devel at lists.freedesktop.org
> > Subject: [systemd-devel] Improving module loading
> > 
> > Hi,
> > 
> > Is there a reason why systemd-modules-load is loading modules
> > sequentially? Few things can happen simultaneously like resolving the
> > symbols etc. Seems like modules_mutex is common on module loads which
> > gets locked up on few occasions throughout the execution of
> > sys_init_module.
> 
> We are actually doing this (in embedded systems which need to be up
> very fast with limited resources) and gained a lot. Mainly, IO and CPU
> can be better utilized by loading modules in parallel (one module is
> loaded while another one probes for hardware or is doing memory
> initialization).

If you have control over your kernel, why not just build the modules
into the kernel, then all of this isn't an issue at all and there is no
overhead of module loading?

greg k-h