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