🚀 go-pugleaf

>
>What you've said is true of present systems, which tag entries with
>process numbers so that they don't have to physically flush the TLB.
>It helps that interrupt routines do not completely flush the TLB, but
>anything reasonably long-lived, like another process, eventually replace
>all of the previous process's TLB entries WHEN SOME OF THEM COULD HAVE
>BEEN REUSED - for shared objects like system space, if they were at the same
>virtual address.

this pushing out of entries will happen ANYHOW.  You have TLB entries
for lots of small segments, or for one big segment.  The effect is the
same, replace-wise.

>What I mean by a single virtual address space is one where all objects have
>unique virtual addresses, where the address ranges of processes do not
>collide, where all objects could at least potentially see each other if it
>were not for the protection system. There'd be no need for a tag then,
>because there is only one translation going on in the system at a time.

I still think this is unrealistic.  The internal workings of MVS demon-
strate the problems that you are trying to solve with bigness.  Bigness
is not an adequate solution.


--Scal