somebody wrote:
> Thus, the safe method is to *not* assume your data will always
> fit into physical memory, even if it will fit into the address space for the
> foreseeable future.

I disagree. You balance the functionality you lose against the speed and/or 
efficiency and/or programming convenience you gain.

 > If the possibility is there that the data may not fit
> into physical memory, you have to ask if you or the OS will be in a better
> position to decide when, if, what and how to page. 

Yep. And you have to balance it against the fact that the OS *will* make 
that decision regardless of whether you want it to or not, and regardless of 
whether you're coding your own paging or not. You also have to balance it 
against the fact that the OS knows who else is using the memory, the 
performance characteristics of the various devices in the machine (including 
page tables, main memory, USB memory, and the disks it may have available to 
swap to), paging behavior of previous executions of the program, and so on. 
I'm not sure you'd gain much by reimplementing all that logic in each 
application and *still* not having the global knowledge the OS has.

> OS, to me, should be the last resort. 

I'm glad all your programs implement their own custom swap files. Me, I'd 
rather have actual improvements in the outputted results, especially given 
that we both already have machines that can handle plenty of memory.

If 64-bit chips and OSes weren't already available, I might agree with you 
that it is important. But I'd rather see POV making full use of all the 
cores than getting slowed down to support someone running a 32-bit OS on a 
64-bit machine.

> I see entirely too many programs today being written with most
> inefficient use of memory since "OS will manage it". With 64 bit address
> space, I am pretty sure that we will see applications that are memory hogs
> and inefficient at levels we have never seen before.

Then don't buy them. :-)

-- 
   Darren New, San Diego CA, USA (PST)
   My fortune cookie said, "You will soon be
   unable to read this, even at arm's length."

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