Messages in this thread | | | Subject | Re: Memory Management - BSD vs Linux | Date | Wed, 13 Aug 1997 14:38:11 +0000 | From | "Ka'Plaagh" <> |
| |
> > How can they only map 'parts' of the virtual address space? Of course > there are problems once you overflow 2 buckets in the hash table but there > are a number of methods for dealing with full hash tables (perhaps not > suitable for use in the kernel - but possible). >
You only have translations for those pages of virtual memory that are in physical memory. The other page table entries (or lack of them) cause page faults when 'not in memory' page accesses occur. These you can fix up in a machine specific way.
> }(Definition of page table: something that maps virtual addresses to > }physical addresses. The IBM hashtables do NOT match that definition, > }because they can only map _parts_ of the virtual address space. As such > }they match the definition of a TLB: a "cache of virtual->physical > > Perhaps I'm a non-IBM-blockhead, but I don't see clearly how you can > support it. > > }translation entries". I dare any IBM blockhead to try to refute this > }without looking silly). >
---------------------------------------------------------------------- David A Rusling Principal Engineer European Semiconductor Applications Digital Equipment Co Ltd., Engineering PO Box 121, Imperial Way, Worton Grange Reading RG2 0TU Linux, Alpha, StrongArm, PCI Tel: UK-(0)1734-204380 Fax: UK-(0)1734-203133 ----------------------------------------------------------------------
| |