Re: Parallel query execution

On Wed, Jan 16, 2013 at 05:04:05PM -0800, Jeff Janes wrote:
> On Tuesday, January 15, 2013, Stephen Frost wrote:
> 
>     * Gavin Flower (GavinFlower@archidevsys.co.nz) wrote:
>     > How about being aware of multiple spindles - so if the requested
>     > data covers multiple spindles, then data could be extracted in
>     > parallel. This may, or may not, involve multiple I/O channels?
> 
>     Yes, this should dovetail with partitioning and tablespaces to pick up
>     on exactly that.  
> 
> 
> I'd rather not have the benefits of parallelism be tied to partitioning if we
> can help it.  Hopefully implementing parallelism in core would result in
> something more transparent than that.

We will need a way to know we are not saturating the I/O channel with
random I/O that could have been sequential if it was single-threaded. 
Tablespaces give us that info;  not sure what else does.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
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