[X-Unix] limit cpu usage

[William H. Magill]

On 29 Nov, 2004, at 08:58, mac2 wrote:
>>> I've googled around, but haven't found an answer to this
>>> question.  I would like to limit the max % cpu a process can
>>> have.  Something similar to ulimit; however, ulimit only allows
>>> limiting the number of cpu seconds a job can run.
>> This is not philosophically possible on a Unix system.
>> What you want to do is a common resource control feature found in 
>> Enterprise Class systems like VMS and MVS, but not Unix.
>
> This is just wrong.  Solaris has the Resource Manager.  AIX has a 
> similar utility built into the OS.
>
>> Over the years, there have been any number of companies who have 
>> written Kernel code to create a "resource management" system for Unix 
>> -- but they tend to cost big bucks and only run on "mainframe class" 
>> Unix boxes ... AND, they never really work the way one expects them 
>> to work anyway.
>> The reason is a long discussion of Operating System theory, but 
>> briefly put, Unix simply does not have the "hooks" necessary to 
>> implement any useful kind of Resource Control.

Neither Solaris nor AIX is Unix ... they are Proprietary Unix variants.

And yes, they do have a resource manager which was added to the OS 
circa 1995; neither one works like the other nor like the version in 
Tru64 Unix (formerly known Digital Unix, formerly known as OSF/1).

T.T.F.N.
William H. Magill
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