On 29-Oct-99 Mike Smith wrote:
>> > That's correct; it's why the ia32 architecture has a '32' in its name.
>> 
>> I don't believe that's true.  I don't have any hard evidence within easy
>> reach, but with the introduction of the Pentium, the address space was
>> increased.  A user process, of course, can only have 4G of addressible
>> space (32-bit addresses) but the OS can map pages of the 4G space into a
>> larger area.

The Pentium and successors can address more than 4G
_physical_ memory, 32 or 64GB, I need to look into
the manual. But that feature needs to be explicitely
enabled.

>> 
>> Something to do with 4MB pages instead of 4K pages.  
>> 
>> Again, I could be wrong on this one.

With extended physical addressing enabled the bigger
page size is 2MB instead of 4 MB.

 
> Think about it for a second.  How big is a pointer?

The Intel architecture still supports segmented memory,
so the effective maximum pointer size is 48 bit.

        Lars


To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message

Reply via email to