Re: INSERT...ON DUPLICATE KEY LOCK FOR UPDATE

On Wed, Sep 25, 2013 at 08:48:11PM -0700, Peter Geoghegan wrote:
> On Wed, Sep 25, 2013 at 8:19 PM, Bruce Momjian <bruce@momjian.us> wrote:
> > This thread had a lot of discussion about bloating.  I wonder, does the
> > code check to see if there is a matching row _before_ adding any data?
> 
> That's pretty much what the patch does.

So, I guess my question is if we are only bloating on a contended
operation, do we expect that to happen so much that bloat is a problem?

I think the big objection to the patch is the additional code complexity
and the potential to slow down other sessions.  If it is only bloating
on a contended operation, are these two downsides worth avoiding the
bloat?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +