Re: sequence indexes

Hannu Krosing wrote:
>
> mlw wrote:
> >
> >
> > Could one run a postgresql process in a lower priority process and
> > perform lazy vacuums without affecting performance all that much?
>
> One must be very careful not to introduce reverse priority problems -
> i.e. a
> lower priority process locking some resource and then not letting go
> while
> higher priority processes are blocked from running due to needing that
> lock.
I understand that, hmm. I wonder if the lock code could boost the priority of a
process which owns a lock.

>
> In my tests 1 vacuum process slowed down 100 concurrent pgbench
> processes
> by ~2 times.

Is that good or bad?

>
> > A live index compaction can be done by indexing the table with a
> > temporary name rename the old index, rename the new index to the old
> > name, and drop the old index.
>
> Isn't this what REINDEX command does ?

REINDEX can't be run on a live system, can it?

>
> ---------------
> Hannu