Re: Simple improvement of "make check" performance

[Ralf Wildenhues]

Hello Sven,

Thanks for the patch.

* Sven Herzberg wrote on Fri, Oct 12, 2007 at 06:29:57PM CEST:
> 
> this patch adds the check targets (eg. check_PROGRAMS) directly to the
> dependencies of check-am, resulting in make spawning one command less
> and better parallel build performance because make can decide whether
> check_PROGRAMS need to be rebuild.
> 
> In a simple example in one of my projects (with "TESTS=" - so that no
> tests are executed) it reduced the overall time for running make check
> in an updated source tree by ~32%.

If you use parallel make with this patch, then it is not guaranteed any
more that `all-am' is completed before any tests are invoked.  For that,
`all-am' would further need to be listed as prerequisite of all check
and check_tests targets.

Further, while the relative speedup of your proposed change sounds nice,
I assume that, in absolute time, it's very small.  Is that correct?  If
yes, then I would not worry so much about it.

> Please tell me if you are interested in this patch and want me to update
> it to cvs HEAD.

No need, it still applies fine.

> PS: Please CC me for replies, as I'm not subscribed to this list.

Sure.

> PPS: I consider this patch being so trivial that no copyright assignment
> should be necessary.

Certainly.

Cheers,
Ralf

>       * automake.in: add the check targets directly to the dependencies of
>       check-am
>       * tests/Makefile.in: changed the Makefile.in according to automake's
>       new output