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On 12/07/2020 09:04, William Kenworthy wrote: |
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> Hi, |
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> |
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> is there a way to change the MAKEOPTS setting on a running emerge? |
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> I am using "-j 5 -l 4" whilst emerging gcc-9.3 but its creating too much |
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> pressure on memory. I expect the emerge to take many more hours but |
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> complete eventually - but reducing it to "-j2" will help other |
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> operations whilst not losing whats already been completed (this is an |
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> old atom N330 with 4G ram and is my gateway/router/firewall/snort/... |
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> and the overload is starting to affect the network throughput |
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> significantly). |
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No. But what you can do is lower its nice level to 19, and CPU and IO |
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priority to "idle". First, find the process IDs of emerge and make: |
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ps aux | grep emerge |
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ps aux | grep make |
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The first number after the user name (which is "root") is the pid. Then |
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do the following for both pids: |
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schedtool -D -n 19 pid |
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ionice -c 3 -p pid |
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ionice is in sys-apps/util-linux, so it's probably already installed. |
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schedtool though is in sys-process/schedtool and it might not be |
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installed. Nothing you can do about that right now. You have to wait it |
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out. ionice should help a bit though. |
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In the future, I *highly* recommend installing schedtool, and then put |
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this in your make.conf: |
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PORTAGE_NICENESS=19 |
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PORTAGE_IONICE_COMMAND="sh -c \"schedtool -D \${PID}; ionice -c 3 -p |
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\${PID}\"" |
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I have used this for many years now. It makes emerge have a virtually |
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imperceptible impact on my system. I can emerge for example gcc or |
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libreoffice with -j4 on my 4 cores/4 threads CPU, and I feel no slowdown |
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at all. This won't help with running out of RAM obviously, but it helps |
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immensely with keeping the system highly responsive. |
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Another thing I recommend is getting rid of "-j5". Use -j4. The "+1" |
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recommendation from decades ago does not apply anymore with modern Linux |
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kernels. You can test this yourself by emerging a smaller package that |
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takes like 2 minutes or so to emerge, and compare times with j4 and j5. |
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Most likely you will see no difference, other than j5 using more RAM. |
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