From: Raffaele Belardi Sent: Wednesday, November 22, 2017 8:12 AM To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] is multi-core really worth it? Jeremi Piotrowski wrote: > That being said: if you do a world rebuild you will have lots of packages > that spend ~40 seconds doing their autoconf run, only to build 2-3 sources > files. On an 8-core machine at work, I get good results using parallel > emerge jobs (emerge -jX). For your 6-core AMD CPU (assuming it actually > has 12 threads) I'd start with 'emerge -j3' and MAKEOPTS='-j12 -l16'. > That should get you a nice speedup, but may require a bit more ram. emerge -j3 is something I did not think of, I'll try it. But won't that break portage's carefully crafted package dependencies? I suppose you could get occasional build failures? I'm using MAKEOPTS=-j7, I thought 2 threads per CPU (hyperthreading?) was an Intel thing only. raffaele There are alot of good tweaks to get by long configure sections, I have an octa core, so for normal updates I use - MAKEOPTS="-j8" # for 8 cores being used per package EMERGE_DEFAULT_OPTS="--jobs 2 --load-average 4" # only starts 2nd job if load average is low. You won't get build failures or dependency problems, portage is built to handle emerging multiple packages that do not depend on each other simultaneously. it will not ever build a dependency and the main program at the same time. PORTAGE_NICENESS="19" # best setting ever, I do some gaming while updating, you mainly only notice install phase if your are loading while the disk queue is full of writes.