Messages in this thread | | | From | (david parsons) | Subject | Re: Kernel cpu selection + other platforms? | Date | 23 Jul 1997 00:53:39 -0700 |
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In article <linux.kernel.Pine.LNX.3.96.970722223623.1839D-100000@sigil.csc.com>, Teunis Peters <teunis@usa.net> wrote: >On 22 Jul 1997, david parsons wrote: > >> In article <linux.kernel.33D3BDE2.404EB0D1@netzblick.com>, >> Roland Steinbach <roland@netzblick.de> wrote: >> >Mike Jagdis wrote: >> > >> >> Why? It is pretty easy to recognise all x86 varieties (other than the >> >> early 486 clones) at run time and simply Do The Right Thing without >> >> asking the user daft questions about whether they have microcode >> >> bug #564 or working frozzle optimizations. >> > >> >_I_ don't want my settings be controlled by an OS, >> >> Whyever not? Resource management is, after all, why you've got an OS >> in the first place. > >CPU settings that drastically change how the OS acts don't count as >resources.... > >Not unless the CPU can be readjusted without affecting running code. >[as an example : try changing page-sizing on the fly... say to 8K pages >from 4K pages....]
You don't need to do that on the fly; you do it just once, when the system is initializing. Unless it's a build option that changes the instructions that the machine execute, or an optimization for the particular processor (adding waitstates so you won't drain a particular pipeline and the like), it's more useful for a general- purpose kernel to have it try and properly set up the cpu at runtime, and have it so you can turn things off manually if they give you problems.
____ david parsons \bi/ I like autoconfiguring systems. \/
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