guidance for using timeout_multiplier?

Ian Lynagh ian at
Sat May 18 22:07:15 CEST 2013

On Wed, May 01, 2013 at 03:38:13PM -0500, Nicolas Frisby wrote:
> Is it sensible for me to add the timeout_multiplier setup function in the
> respective all.T files if I can reproduce the time out? It looks like 3
> seconds ought to be fine for the ones I've investigated so far, so I was
> thinking of passing 0.01.

timeout_multiplier should only be use to make timeouts longer, not
shorter. Otherwise, on slow platforms, tests will timeout even when they
would otherwise pass.

If slow tests are a problem, and fixing them isn't an option, then I'd
suggest making a skip_broken helper (similar to expect_broken, except it
skips the test rather than expecting the wrong result) and marking them
something like
    when(opsys('darwin'), skip_broken(nnn))
It's important to use a skip_broken rather than just skip, to ensure
that a ticket is filed and the test is linked to it.

Ian Lynagh, Haskell Consultant
Well-Typed LLP,

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