Do you mess with kernel parameters?

SlowCoder

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What kernel parameters do you commonly change from default to unbreak something, or to make your system better?

Example: I use vm.swappiness=10 to reduce swapping to my SSD.
 


KGIII

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Only if I have to. Which, well, I haven't had to for quite some time. The last time I had to, I had to add noapic to the boot parameters, which should only be a temporary 'fix' until things like the BIOS are updated. By the time I retired the device, it had not been updated to a point where I could remove the command.

If I didn't use it, it'd power off erratically. Fortunately, it was nice enough to leave clear errors in the logs.
 

CrazedNerd

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Hmmm, very interesting. When I change the grub timeout, is that a "configuration/bash parameter"? I've never altered the linux kernel before.
 
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SlowCoder

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Hmmm, very interesting. When I change the grub timeout, is that a "configuration/bash parameter"? I've never altered the linux kernel before.
Well, I was actually asking about running kernel parameters, such as those listed in sysctl. But I'm also interested in learning more about boot parameters.
 

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SlowCoder

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KGIII

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That's a good link. But what I'm actually looking for is settings people may use in the real world.

We do. Those are all probably used by someone. Heck, up above I gave you an instance of me using one of them in the real world -- 'noapic' to be specific. They're added during the boot process,

You'll find the web littered with people suggesting 'em for fixes for problems. Just because *you* don't use them doesn't mean nobody does.

Gotta backlit keyboard that won't work, there's a parameter for that. Getting IRQ errors in your logs? There's like a dozen of 'em you can try. Every time we tell someone to modify their grub and add a boot parameter, odds are that it's on the list somewhere.
 

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SlowCoder

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We do. Those are all probably used by someone. Heck, up above I gave you an instance of me using one of them in the real world -- 'noapic' to be specific. They're added during the boot process,

You'll find the web littered with people suggesting 'em for fixes for problems. Just because *you* don't use them doesn't mean nobody does.

Gotta backlit keyboard that won't work, there's a parameter for that. Getting IRQ errors in your logs? There's like a dozen of 'em you can try. Every time we tell someone to modify their grub and add a boot parameter, odds are that it's on the list somewhere.
Yes, think of this a sort of social thread, not me asking how to do stuff. Things like "Hey, yeah, I fixed this problem using that setting the other morning! Saved my hide!" I'm curious how often people find uses for the parameters, and in what ways.

I personally haven't had much need to use the kernel params. But the one I mentioned, vm.swappiness is useful to me because I don't want my machine spamming my SSD all the time.
 
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