1 Feb
2012
1 Feb
'12
4:17 a.m.
Mouse wrote:
Depends on what you're doing.
I've written plenty of code for which 256-entry tables are totally
practical but 65536-entry tables are somewhere between difficult and
completely out of the question. (And even without such tables, related
remarks apply; for example, enumerating all pairs of chars is often
reasonable for 8-bit chars but utterly out of reach for 16-bit chars.)
It depends on how much memory is available.
Even on the PDP-11, FORTRAN under RT-11 supports
virtual arrays of MB of memory. Since a 65536 entry
table of words needs only 128 KB, that would be very
feasible. Plus under E11, it is very easy to run a PDP-11
which makes explicit use of PC memory. I have requested
up to 1280 MB of PC memory under Windows XP
when I run RT-11 and I want to sieve for Prime Numbers.
I does come in handy and it would be possible to make
a real device under a real DEC PDP-11 with 4 GB of
memory supported with the same sort of IOPAGE
registers for access to the PC memory from inside
an RT-11 program.
Jerome Fine