Loading Modules Automatically
The so-called kernel daemon kerneld is an especially useful feature. With the help of this daemon, the kernel can load needed device drivers and other modules automatically and without manual intervention from the system administrator. If the modules are not needed after a period of time (60 seconds), they are automatically unloaded as well.
In order to use kerneld, you need to
turn on support for it during kernel configuration, and you also
need the System V IPC
option. kerneld must be started from one of
the system startup files; newer distributions are doing this
automatically.
Modules that need other modules must be correctly listed
into
/lib/modules/
kernelversion
/modules.dep
, and there must be aliases for the major and minor number in /etc/conf.modules
. See the documentation from the modules
package for further information.
If a module has not been loaded manually with
insmod or modprobe, but
loaded automatically from kerneld, the module
is listed
with the addition (autoclean)
in the
lsmod output. This tells you that
kerneld will remove the module if it has not
been used for more than one minute.
One last word about kerneld: In the latest kernels, kerneld is obsolete, because there is a new kernel feature called kmod that does the same (by running a separate kernel thread that loads the modules on demand). Still, running kerneld does not hurt.
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