Tuning the kernel through the proc filesystem
The behavior of the Linux kernel can be changed on the fly using the proc filesystem.
For basic information on changing kernel parameters through the /proc filesystem, read Documentation/sysctl/* in the Linux source.
See some examples of kernel parameter manipulations in /etc/init.d/networking and Странные проблемы доступа на некоторые web-сайты, раздел 3.7.5.
See sysctl.conf(5) for how to set up the boot time kernel configuration through /proc filesystem with /etc/init.d/procps.sh script usually run from /etc/rcS.d/S30procps.sh.