Datasheet

“main” (Installation and Administration) — 2004/6/25 — 13:29 — page 238 — #264

lsmod Shows which modules are currently loaded as well as how many

other modules are using them. Modules started by the kernel daemon

are tagged with autoclean. This label denotes that these modules

will automatically be removed once they reach their idle time limit.

modinfo Shows module information.

9.4.3 /etc/modprobe.conf

The loading of modules is affected by the ﬁles /etc/modprobe.conf and

/etc/modprobe.conf.local and the directory /etc/modprobe.d.

See man modprobe.conf. Parameters for modules that access hardware

directly must be entered in this ﬁle. Such modules may need system-

speciﬁc options (e.g., CD-ROM driver or network driver). The param-

eters used here are described in the kernel sources. Install the package

kernel-source and read the documentation in the directory /usr/src/

linux/Documentation/.

9.4.4 Kmod — the Kernel Module Loader

The kernel module loader is the most elegant way to use modules. Kmod

performs background monitoring and makes sure the required modules are

loaded by modprobe as soon as the respective functionality is needed in

the kernel.

To use Kmod, activate the option ‘Kernel module loader’ (CONFIG_KMOD)

in the kernel conﬁguration. Kmod is not designed to unload modules auto-

matically; in view of today’s RAM capacities, the potential memory savings

would be marginal. For reasons of performance, monolithic kernels may be

more suitable for servers that are used for special tasks and need only a few

drivers.

9.5 Settings in the Kernel Conﬁguration

All the kernel’s conﬁguration options cannot be covered here in de-

tail. Make use of the numerous help texts available on kernel conﬁgura-

tion. The latest kernel documentation is always in /usr/src/linux/

Documentation/.

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9.5. Settings in the Kernel Conﬁguration