Re: Reviewing freeze map code

Andres Freund wrote:

> On 2016-05-06 14:17:13 -0700, Joshua D. Drake wrote:
> > How do I test?
> > 
> > Is there a script I can run?
> 
> Unfortunately there's few interesting things to test with pre-made
> scripts. There's no relevant OS dependency here, so each already
> existing test doesn't really lead to significantly increased coverage
> being run by other people.  Generally, when testing for correctness
> issues, it's often of limited benefit to run tests written by the author
> of reviewer - such scripts will usually just test things either has
> thought of.  The dangerous areas are the ones neither author or reviewer
> has considered.

We touched this question in connection with multixact freezing and
wraparound.  Testers seem to want to be given a script that they can
install and run, then go for a beer and get back to a bunch of errors to
report.  But it doesn't work that way; writing a useful test script
requires a lot of effort.  Jeff Janes has done astounding work in these
matters.  (I don't think we credit him enough for that.)

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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