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The system motherboard has a programmable interval timer which is used as the system clock; this generates 100 clock interrupts or clock ticks per second (this value is defined as the constant HZ in the header file /usr/include/sys/param.h).
The tunable kernel parameter MAXSLICE sets the maximum time slice for a process. Its default value is 100 clock ticks (one second). The range of permissible values is between 25 and 100 (between one quarter of a second and one second).
The effect of reducing MAXSLICE is
to allow each process to run more often
but for a shorter period of time.
This can make interactive applications running on the system
seem more responsive.
However, you should note that
adjusting the value of MAXSLICE
may have little effect in practice.
This is because most processes will need to sleep
before their time slice expires
in order to wait for an I/O resource.
Even a calculation-intensive process,
which performs little I/O,
will tend to be replaced on the CPU
by processes woken
when an I/O resource becomes available.