Re: [RFC][PATCH] new timeofday core subsystem (v.A0)

Dominik Brodowski
2004-09-15T08:55:38Z

On Wed, Sep 15, 2004 at 01:04:04AM -0700, George Anzinger wrote:
> >One could do this but we want to have a tickless system. The tick is only
> >necessary if the time needs to be adjusted.
>
> I really think a tickless system, for other than UML systems, is a loosing
> thing. The accounting overhead on context switch (which increases as the
> number of switchs per second) will cause more overhead than a periodic
> accounting tick once a respectable load appears.
^^^^^^^^^^^^^^^^

On a largely idle system (like notebooks on battery power in typical use)
the accounting overhead will be less a problem. However, the CPU being
woken up each millisecond will cause an increased battery usage. So if
the load is less than a certain threshold, tickless systems do make much
sense.

Dominik