Re: Logical tape pause/resume

On 4 October 2016 at 12:47, Heikki Linnakangas <hlinnaka@iki.fi> wrote:

>> Why not just make each new run start at a block boundary?
>> That way we waste on average BLCKSZ/2 disk space per run, which is
>> negligible but we avoid any need to have code to read back in the last
>> block.
>
>
> Hmm. You'd still have to read back the last block, so that you can update
> its next-pointer.

If each run is in its own file, then you can skip that bit.

And we do want the sort to disk to use multiple files so we can
parallelize I/O as well as CPU.

So since we know we'll want multiple files, we should be thinking
about how to split things up between files.

-- 
Simon Riggs                http://www.2ndQuadrant.com/
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