[systemd-devel] Improving module loading

[Umut Tezduyar Lindskog]

On Tue, Dec 16, 2014 at 4:59 PM, Tom Gundersen <teg at jklm.no> wrote:
> On Tue, Dec 16, 2014 at 4:54 PM, Umut Tezduyar Lindskog
> <umut at tezduyar.com> wrote:
>> The other thought is, what is the preferred way of loading modules
>> when they are needed.
>
> Rely on kernel autoloading. Not all modules support that yet, but most
> do. What do you have in mind?

We have some modules that we don't need them to be loaded so early. We
much prefer them to be loaded when they are needed. For example we
don't need to load the SD driver module until the service that uses SD
driver is starting. With this idea in mind I started some
investigation. Then I realized that our CPU utilization is not that
high during module loading and I blame it to the sequential loading of
modules. I am thinking this can be improved on systemd-modules-load
side.

>
>> Do they have to be loaded on ExecStartPre= or as
>> a separate service which has ExecStart that uses kmod to load them?
>> Wouldn't it be useful to have something like ExecStartModule=?
>
> I'd much rather we improve the autoloading support...

My understanding is autoloading support is loading a module if the
hardware is available. What I am after is though loading the module
when they are needed.

Umut

>
> Cheers,
>
> Tom