Re: CommitDelay performance improvement - Mailing list pgsql-hackers

From ncm@zembu.com (Nathan Myers)
Subject Re: CommitDelay performance improvement
Date
Msg-id 20010223172046.V624@store.zembu.com
Whole thread Raw
In response to Re: CommitDelay performance improvement  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: CommitDelay performance improvement  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
On Fri, Feb 23, 2001 at 06:37:06PM -0500, Bruce Momjian wrote:
> > When thinking about tuning N, I like to consider what are the interesting 
> > possible values for N:
> > 
> >   0: Ignore any other potential committers.
> >   1: The minimum possible responsiveness to other committers.
> >   5: Tom's guess for what might be a good choice.
> >   10: Harry's guess.
> >   ~0: Always delay.
> > 
> > I would rather release with N=1 than with 0, because it actually
> > responds to conditions. What N might best be, >1, probably varies on
> > a lot of hard-to-guess parameters.
> >
> > It seems to me that comparing various choices (and other, more
> > interesting, algorithms) to the N=1 case would be more productive
> > than comparing them to the N=0 case, so releasing at N=1 would yield
> > better statistics for actually tuning in 7.2.
>
> We don't release code because it has better tuning opportunities for
> later releases. What we can do is give people parameters where the
> default is safe, and they can play and report to us.

Perhaps I misunderstood.  I had perceived N=1 as a conservative choice
that was nevertheless preferable to N=0.

Nathan Myers
ncm@zembu.com


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