Fundamental defect of the concept of shared libraries

[Tony Shaughnessy]

In article <216 at titccy.cc.titech.ac.jp> mohta at necom830.cc.titech.ac.jp (Masataka Ohta) writes:
>In article <1991May20.090857 at wsl.dec.com> mcnally at wsl.dec.com writes:
>
>>|> You don't know about hardware enough. Because address translation is time
>>|> consuming, fast cache is always indexed by virtual address. Thesedays,
>>|> virtually indexed cache is quite common.
>
>>|> So, if you want shared libraries, you can put it only on slower machines.
>
>>How about MIPS R3000/R4000?  Maybe that's not fast enough.
>
>The primary cache of R4000 is virtually indexed and physically tagged.
>That is, it can't map different virtual addresses to a physical address.
>
>							Masataka Ohta

I quote from the book "MIPS Risc Architecture" by Gerry Kane, Prentice Hall,
1989, page 4-1.

	"The mapping of these extended, process-unique virtual addresses to
	physical addresses need not be one-to-one; virtual addresses of two
	or more different processes may map to the same physical address."

Tony Shaughnessy
tonys at pyra.co.uk