Re: Threaded Sorting

scott.marlowe wrote:
> > We haven't thought about it yet because there are too many buggy thread
> > implementations.  We are probably just now getting to a point where we
> > can consider it.  However, lots of databases have moved to threads for
> > all sorts of things and ended up with a royal mess of code.  Threads
> > can only improve things in a few areas of the backend so it would be
> > nice if we could limit the exposure to threads to those areas;  sorting
> > could certainly be one of them, but frankly, I think disk I/O is our
> > limiting factore there.  I would be interested to see some tests that
> > showed otherwise.
> 
> Wouldn't the type of disk subsystem really make a big difference here?
> 
> With a couple of U160 cards and a dozen 15krpm hard drives, I would 
> imagine I/O would no longer be as much of an issue as a single drive 
> system would be.
> 
> It seems like sometimes we consider these issues more from the one or two 
> SCSI drives perspective insted of the big box o drives perspective.

Yes, it is mostly for non-RAID drives, but also, sometimes single drives
can be faster.  When you have a drive array, it isn't as easy to hit
each drive and keep it running sequentially.  Of course, I don't have
any hard numbers on that.  ;-)

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