On Sun, April 25, 2010 20:55, Tom Lane wrote:
>
> That seems weird.  Why do most of the runs show primary and standby
> as having comparable speed, but a few show the standby as much slower?
> The parameters for those runs don't seem obviously different from cases
> where it's fast.  I think there might have been something else going on
> on the standby during those runs.  Or do you think those represent
> cases where the mystery slowdown event happened?
>

the strange case is the scale 100 standby's slow start, followed by
a steady increase during -c 1, then -c 10, and finally getting up to speed
with -c 20 (and up).  And these slow-but-growing standby series are interspersed
with normal (high-speed) primary series.

I'll try to repeat this pattern on other hardware; although
if my tests were run with faulty hardware I wouldn't know how/why
that would give the above effect (such a 'regular aberration').


testing is more difficult than I thought...


Erik Rijkers

In response to

• Re: testing HS/SR - 1 vs 2 performance at 2010-04-25 18:55:02 from Tom Lane

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• Re: testing HS/SR - 1 vs 2 performance at 2010-04-26 07:43:09 from Simon Riggs

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