On Thu, Jun 11, 2009 at 11:14 PM, Michael Buesch<mb@xxxxxxxxx> wrote: > On Thursday 11 June 2009 23:10:52 Luis R. Rodriguez wrote: >> On Thu, Jun 11, 2009 at 2:05 PM, Michael Buesch<mb@xxxxxxxxx> wrote: >> > On Thursday 11 June 2009 20:48:13 Luis R. Rodriguez wrote: >> >> On Thu, Jun 11, 2009 at 2:29 AM, Jan Kiszka<jan.kiszka@xxxxxx> wrote: >> >> > Hi, >> >> > >> >> > while watching compat-wireless-2009-06-11 doing baby-steps building all >> >> > its modules, I wonder what slows this down so horribly. No other >> >> > external module build package I know is that slow (I would say *at >> >> > least* one order of magnitude slower than normal). Is this really required? >> >> > >> >> > [ Hurray, it's finished! ] >> >> >> >> I think the many depmod -ae are the culprit. This is in place to >> >> account for all the crap of madwifi which may be present or older >> >> drivers which have been renamed. >> >> >> >> This could be improved. Patches are welcomed. >> >> >> >> Ps. Try building with make -j 2, etc. >> > >> > -j does not help. It will hardly build in parallel then. >> >> It works swell for me. The only thing that does not build in parellel >> is the autoconf stuff but after its done with that step everything >> builds as expected with -j 2. >> >> > There's something >> > that serializes most of it (implicitly). >> >> You certain its just not the first part? I had written some patches to >> make the first autoconf step into another step to then allow make -j >> foo to work without a warning but that would involve another step. The >> -j option does work for me though. > > Well, I never measured it, but I don't see any advantage when using -jX. Maybe > that is because forever equals forever+1. > > What I do see, though, is that the per-cpu load is much higher when building the > kernel itself with the same -j parameter. Actually, most of the slowness comes from stage 2 of the module build. For me, stage 1 runs through rather fast (and -jX accelerates it quite well), but stage 2 is serialized, and there is a long wait between individual files. This wait is about a second on 2.6.28 for me in vmware, but over 5 seconds (!!!) on 2.6.29. I've tried multiple distros, and the time difference is consistent. (BTW stage 2 is serialized in a full kernel build as well, though there is no reason why it should be so; but no "wait" between steps is observed - in fact, the second stage of a full 2.6.29 kernel build completes faster for me than the second stage of compat-wireless on 2.6.29!) -- Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-) -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
