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Re: Ideal Swap Partition Size



On Sat, Jan 24, 2009 at 2:52 PM, Patrick O'Callaghan
<pocallaghan gmail com> wrote:
> On Sat, 2009-01-24 at 11:49 -0800, Nifty Fedora Mitch wrote:
>>  Research TLB, here is a link to start with:
>>
>>    http://en.wikipedia.org/wiki/Translation_lookaside_buffer
>>
>> With a TLB and clever kernel software a process has the luxury of
>> living
>> in a virtual address space and not having to relocate itself to run.
>
> You're confusing TLB with the page mapping hardware as a whole. The TLB
> is simply a cache to make the mapping faster.

I could be confused or just using 30 year old language when we
had to build our own TLB/MMU out of fast static RAMs and TTL chips.

The TLB is the critical and necessary  first step in building a VM system.
Restarting instructions is the necessary functionality to build a demand
paged VM system.
Full memory management units (MMU) reach out to cache, and enforce attributes
like read only, cacheable, uncacheable, write through, TLB sets, atomic
operations, bus arbitration, and more.

By standers might wish to scan this URI:
     http://en.wikipedia.org/wiki/Memory_management_unit

The student might search out the National Semiconductor NS32332
or the Motorola MC68451 data books in a library or on line.  These
early books are as much tutorial ad anything.   Also the MIPS 3000
data book is worth looking at.   The MIPS 3000 MMU was minimal and the
documentation was great at discussing how to build complex and
rich memory management models from a minimum but sufficient
set of functionality.





-- 
        NiftyFedora
        T o m   M i t c h e l l


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