Re: Linux-Kernel Archive: No 100 HZ timer !

From: Michael Raymond (mraymond@sgi.com)
Date: Fri Apr 13 2001 - 07:55:53 EST


On Fri, Apr 13, 2001 at 08:20:56AM -0400, Mark Salisbury wrote:
> inner loop, i.e. interrupt timer code should never have to convert from some
> real time value into number of decrementer ticks in order to set up the next
> interrupt as that requires devides (and 64 bit ones at that) in a tickless
> system.
>
> this is why any variable interval list/heap/tree/whatever should be kept in
> local ticks. frequently used values can be pre-computed at boot time to
> speed up certain calculations (like how many local ticks/proc quantum)

    What about machines without synchronized local ticks? We're going to
have to end up doing conversions anyway because of drift and machines
without even the same speed CPUs. A time based system using local cached
values such as cycles_per_usec would better be able to handle this.
                                                                                     Michael

-- 
Michael A. Raymond              Office: (651) 683-3434
Irix Core Kernel Group
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This archive was generated by hypermail 2b29 : Sun Apr 15 2001 - 21:00:21 EST