I think this has triggered a workable idea.

Given a 2GB buffer of (minimum) 8-byte records = 268,435,456 records; using 1-bit per record requires 32MB. Well within my 10%.

So, what can I record with 1-bit?

My first though is that I can record whether this record is contiguous with the preceding one. Ie. Is is equal to it; or exactly one greater. In effect, contiguous runs of 1-bits become chunks of the buffer(s) that can be translocated to their final position en-masse.

And (I think) by processing down those bitmaps in parallel (though not lock-step), and knowing the first value in each of the two buffers, it gives me a a straight forward map of how things have to be moved into their final positions.

Does that convert the original O(N2) process into an O(2(or 3?)N) process?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I'm with torvalds on this
In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked

In reply to Re^4: [OT] A measure of 'sortedness'? by BrowserUk
in thread [OT] A measure of 'sortedness'? by BrowserUk

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