🚀 go-pugleaf

In article <44p44b$aqe@news.dtc.hp.com>, shoens@hpl.hp.com (Kurt Shoens) writes:
|> Organization: Hewlett-Packard
|> 
|> Or another way to look at is economically.  Suppose in the future memory
|> system prices drop to 1 cent per megabyte.  Then 64 bits worth of physical
|> memory costs $160 billion.  Carrying it further, at .01 cents/megabyte it's
|> still $1.6 billion.
|> 
|> Forget your children's college tuition costs.  Start saving now for the
|> memories of the future!

True ... but easily confusing.  I doubt that anybody intends to build
2**64 byte memories any time soon, hence the cost of such things is meaningless.

The leading edge of refrigerator-sized microprocessor SMP systems has
already gotten into the 2**33 or 2**34-byte range (8GB-16GB),
and customers have purchased such things.  That doesn't mean everybody
wants to do this, but it does mean that >4GB memories are hardly
lunatic-fringe.

One does *not* need to have 64-bit flat virtual addressing to support 2**33
bytes, just as PDP-11s didn't need 20-bit virtual addressing to support
1MB of physical memory ... but it certainly makes life better for the OS folks.

-- 
-john mashey    DISCLAIMER: <generic disclaimer, I speak for me only, etc>
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