<div dir="ltr"><div class="gmail_extra"><br /><div class="gmail_quote">On Fri, Oct 3, 2014 at 3:10 PM, Bruce Momjian
<spandir="ltr"><<a href="mailto:bruce@momjian.us" target="_blank">bruce@momjian.us</a>></span> wrote:<br
/><blockquoteclass="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span
class="">OnFri, Oct 3, 2014 at 02:07:45PM -0400, Bruce Momjian wrote:<br /> > On Fri, Oct 3, 2014 at 03:00:56PM
-0300,Arthur Silva wrote:<br /> > > I remember Informix had a setting that had no description except "try<br
/>> > different values to see if it helps performance" --- we don't want to do<br /> > > that.<br
/>> ><br /> > > What if we emit a server message if the setting is too low? That's how<br /> >
> we handle checkpoint_segments.<br /> > ><br /> > > Not all GUC need to be straight forward to
tune.<br/> > > If the gains are worthy I don't see any reason not to have it.<br /> ><br /> > Every GUC add
complexityto the system because people have to understand<br /> > it to know if they should tune it. No GUC is
zero-cost.<br/><br /></span>Please see my blog post about the cost of adding GUCs:<br /><br /> <a
href="http://momjian.us/main/blogs/pgblog/2009.html#January_10_2009"
target="_blank">http://momjian.us/main/blogs/pgblog/2009.html#January_10_2009</a><br/><div class="HOEnZb"><div
class="h5"><br/> --<br /> Bruce Momjian <<a href="mailto:bruce@momjian.us">bruce@momjian.us</a>> <a
href="http://momjian.us"target="_blank">http://momjian.us</a><br /> EnterpriseDB <a
href="http://enterprisedb.com"target="_blank">http://enterprisedb.com</a><br /><br /> + Everyone has their own god.
+<br/></div></div></blockquote></div><br /></div><div class="gmail_extra">That's true Bruce (nice post, it was a good
reading).<br/>But how can we ignore 25%+ improvements (from 8 to 24)?<br />At very least we should delivery some pretty
gooddefaults.<br /></div></div>