make check / dbgutil performance ...

On Fri, 2015-05-29 at 13:11 +0200, Bjoern Michaelsen wrote:
> On Fri, May 29, 2015 at 10:02:56AM +0100, Michael Meeks wrote:
> >     It is clearly great to run 'make check' before pushing (just fixing
> > some results from CI) - however, to assume that everyone has a 32 core
> > machine (I have 4 not-so-strong cores) 32/4 * 2m -> 16m (not so far from
> > 15 minutes ;-).

        It turns out I seriously under-estimated how long 'make' check' takes
for me:

$ time make check PARALLELISM=9999
real    31m37.282s
user    92m2.229s
sys     2m54.219s

        That's for a dbgutil build, and I'm using the machine - but not heavily
(no compilation etc - just some E-mail / web).

        Without dbgutil we get:

real    12m45.145s
user    28m47.321s
sys     2m34.849s

        Which is better, but still not 3x minutes.

> On an antique notebook with a mid-level second generation mobile i7 you get
> below 400EUR on ebay.

        Then again - I don't have an 8x core i7 - which no matter how
apparently cheap they are 2nd hand doesn't seem to me that reasonable.

        So - it seems to me that we could usefully invest in improving 'make
check' performance; not least by loosing 'sleeps' - I guess more
profiling is in order.

        Oh ! and - I suspect the ~3x slower dbgutil issue can be fixed with
this easy hack:

        https://bugs.documentfoundation.org/show_bug.cgi?id=91872

        Which is also rather easy I hope.

        ATB,

                Michael.

-- 
 michael.meeks@collabora.com  <><, Pseudo Engineer, itinerant idiot