Re: Reducing relation locking overhead - Mailing list pgsql-hackers

From Stephen Frost
Subject Re: Reducing relation locking overhead
Date
Msg-id 20051202030333.GB6026@ns.snowman.net
Whole thread Raw
In response to Re: Reducing relation locking overhead  (Christopher Kings-Lynne <chriskl@familyhealth.com.au>)
List pgsql-hackers
* Christopher Kings-Lynne (chriskl@familyhealth.com.au) wrote:
> >4. The only reason we need to take relation-level locks on indexes
> >at all is to make the world safe for REINDEX being done concurrently
> >with read-only accesses to the table (that don't use the index being
> >reindexed).  If we went back to requiring exclusive lock for reindex we
> >could forget all about both #2 and #3.  Particularly for updates of
> >relations with lots of indexes, this could be a pretty significant win.
> >However we'd definitely be giving up something that was seen as a
> >feature at one point, so I'm not sold on this idea ... unless someone
> >can see a way to reduce the overhead without giving up concurrent
> >REINDEX.
>
> Surely in the real world REINDEX is run so rarely compared to all those
> other operations it'd be a win...

Yeah, except that in the real world you don't want to bring everything
to a halt while you do a REINDEX.  For my use cases it'd be fine but I
could see cases where it wouldn't be.  Kinda makes me wish we could give
the user the option at runtime somehow but I'm not sure that could be
done...
Thanks,
    Stephen

pgsql-hackers by date:

Previous
From: "Greg Sabino Mullane"
Date:
Subject: Re: Windows installation notes
Next
From: "Pollard, Mike"
Date:
Subject: Re: generalizing the planner knobs