Re: Disk scheduling policy (Re: NEW_BUFQ_STRATEGY)

* Thor Lancelot Simon <[email protected]> [031201 15:12] wrote:
> 
> Matt Thomas suggested simply starting at whichever end of the other
> queue is nearer the current head position, which is an interesting 
> idea.  I was pondering zoning the disk, so you'd have multiple "queues"
> on each side of the "delayed"/"normal" divide, and could try to switch
> to the one nearest the block you're currently at, but that adds
> significant complexity.  I'm going to implement a couple of different
> things and measure them for different workloads.

That can lead to starvation.  The best bet is to keep it simple and
make sure that you sweep back and forth, never doubling back.

-- 
- Alfred Perlstein
- Research Engineering Development Inc.
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