On Thursday 27 January 2011 19:56:23 Allan Gottlieb wrote: > On Thu, Jan 27 2011, Neil Bothwick wrote: > > On Thu, 27 Jan 2011 17:09:27 +0200, Nikos Chantziaras wrote: > >> > So on a 20 package world update, only 19 are faster while the 20th > >> > runs at the same speed? Where's the loss there? Even if the last were > >> > slower, it would be worth it. > >> > >> Given the amount of time unpack/configure/install of most packages > >> needs (very short), my observation is that it would not be worth it. > > > > Even if that were true, how much time would you have to save to justify > > adding -j 2 to EMERGE_DEFAULTS in make.conf? > > > > But it's not true, large packages spend a lot of time on these phases of > > the install. > > OK I'm convinced since I know that those phases do take noticeable time. > > I have a "4" processor i7 model 620 (2 cores, doubled for > hyperthreading) and have set MAKEOPTS="-j5". > If I add -jobs=2 to EMERGE_DEFAULT_OPTS, should I lower > MAKEOPTS to 3 (to 4)? > > thanks, > allan
You could, as if you leave it at -j5, you can end up with 2 * 5 = 10 processed, eg: similar as if running with MAKEOPTS="-j10" I think the option that YoYo came with is a good compromise: # MAKEOPTS="-j -l5" emerge -j --load-average=5 Next time I am doing a big upgrade, I'm going to test that to see how it behaves. -- Joost
