Re: autovacuum multiworkers, patch 5

ITAGAKI Takahiro wrote:
> > > >Yes, that's correct.  Per previous discussion, what I actually wanted to
> > > >do was to create a GUC setting to simplify the whole thing, something
> > > >like "autovacuum_max_mb_per_second" or "autovacuum_max_io_per_second".
> > > >Then, have each worker use up to (max_per_second/active workers) as much
> > > >IO resources.
> >
> > One thing I forgot to mention is that this is unlikely to be implemented
> > in 8.3.
>
> This is a WIP cost balancing patch built on autovacuum-multiworkers-5.patch.
> The total cost of workers are adjusted to autovacuum_vacuum_cost_delay.
>
> I added copy of worker's cost parameters to the shared WorkerInfo array.
> A launcher and each worker reads and writes the copied parameters when
> a worker starts a vacuum job or exit the process. Workers assign their local
> VacuumCostDelay from the shared value every sleep in vacuum_delay_point().

Thanks!  I had already incorporated the foreach_worker changes into my
code, and later realized that there's an important bug regarding the
PGPROC of the workers, so I've reworked the patch, which meant that the
foreach_worker() macro went away completely.

I'll put it your changes in my current WIP patch; if you do any further
work on it, please let me have it to include it in the latest work.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.