Re: Going from 32M to 48M, Linux crawls!
H. Peter Anvin (hpa@transmeta.com)
3 Jun 1996 15:31:00 GMT
In article <31B2AB60.531D@yallara.cs.rmit.edu.au>,
Lawrence Chim <ychim@yallara.cs.rmit.edu.au> wrote:
>>
>> Looks like your cache won't work with the extra 16 MB. Depending on the
>> kernel's memory mapping strategy, the code which is accessed most, is
>> now located in un-cached memory, so your system _must_ crawl.
>>
>> Try changing your CMOS settings / adding more cache.
>>
>
>Does it mean that Linux can only use cached memory?
>I don't know why if it is the case. As we all know that
>the only problem with un-cached memory is the SPEED.
>
No, it means Linux works faster with less, cached memory than with
more, uncached. Uncached memory (like ISA memory etc) can be used
efficiently by Linux if you configure a RAM disk in that memory region
and use it as swap space.
Needless to say, if you can get your MB to cache your RAM properly you
are much better off.
-hpa