[Bizgres-general] Off-list Re: [ENG] Re: Statement Queuing take II - Resource Scheduling (Running with cost and cursors)

[Luke Lonergan]

Gavin, 

> A novel way to solve this problem might be to introduce the 
> concept of a pool of temporary storage devices. Say we had 4 
> partitions in our pool and
> 4 concurrent queries doing external sort then we could do 
> each concurrently without conflicting IO (IO bus aside). This 
> will not scale but it does have the benefit of zero overhead.

It's a structured way to add more resources AFAICS.

You could implement the timesharing at that layer instead, but then
you'd lose the nice control we're building into the statement queueing
layer.

The timesharing mechanism is something we can implement after we
implement the resource queueing, but we can definitely see that we'll
need some mechanism to work around the single threaded queue stuck with
long running query problem.

- Luke