30 Oct
2015
30 Oct
'15
2:14 p.m.
On 10/30/2015 01:40 PM, Fred Cisin wrote:
I always assigned them a problem of writing a sort for
a file/dataset
too big to fit into memory. They literally refused to understand
that a dataset could exist that would be too large to fit into
memory. A couple of students wrote a letter to the college
administration complaining about me and the department and our
"out-dated" curriculum, insisting that "in the real world, the proper
solution to a file too big for memory is to replace the computer with
a bigger one." I was actually called on the carpet to answer the
charge! That was trivially easy when I pointed out to the chancellor
how much it would COST to equip the student homework computer labs
with computers capable of holding a national telephone directory in
memory.
How times change. Most programmers of my era, would do it the "old" way
by habit--read in bits of the dataset. It took quite a bit of
relearning that mapping a file into a 48-bit address space and operating
on the data directly, letting the pager do the bookkeeping could render
what at first started out to be a fairly complicated job, very simple.
--Chuck