Does the sequential pass of the buffers have to be done first?

Yes.

Perhaps the more important question is in the nature of the items.

I think I mentioned "call them numbers". The point is that they are fixed length records; so even if there are multiple numbers, or a string, the comparison function will be very simple, so not much mileage there.

I got the impression your data was all in memory however.

Indeed. Whilst the data originates on disk and is bigger than memory; the two buffers being merged here are both fully in memory, but combined are close to the limits of memory, hence not enough space to perform the n-way merge.

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^2: [OT] A measure of 'sortedness'? by BrowserUk
in thread [OT] A measure of 'sortedness'? by BrowserUk

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