:: Re: [dyne:bolic] swappiness
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Author: Alvaro Steiger
Date:  
To: dynebolic mailinglist
Subject: Re: [dyne:bolic] swappiness
I think he's talking about another thing. Extrated this from fosswire:

Most modern operating systems are capable of using a file or partition known
as a *swap* or *paging* file. Most Linux distributions will also install one
for you by default. This file is used to extend the amount of available RAM
by writing some of it to your hard drive.

There's just one problem: hard drives are slow. We can't fix that problem
yet, but we can avoid it. The Linux kernel provides a tweakable setting that
controls how often the swap file is used, called *swappiness*. A
swappinesssetting of zero means that the disk will be avoided unless
absolutely
necessary (you run out of memory), while a swappiness setting of 100 means
that programs will be swapped to disk almost instantly.

My Ubuntu system comes with a default of 60, meaning that the swap file will
be used fairly often if the memory usage is around half of my RAM. You can
check your own system's swappiness value by running:

cat /proc/sys/vm/swappiness

My HDD is insanely slow and I have 2 GB of RAM, so I'd like to turn that
down to 10 or 15. The swap file will then only be used when my RAM usage is
around 80 or 90 percent. To change the system swappiness value, open *
/etc/sysctl.conf* as root. Then, change or add this line to the file:

vm.swappiness = 15

Reboot for the change to take effect. You can also change the value while
your system is still running:

sysctl vm.swappiness=15

However, you won't get the full effect of rebooting because there is
probably already memory stored in swap that won't instantly be moved out.

Update: Readers have noted that you can clear your swap by running *swapoff
-a* and then *swapon -a* as root instead of rebooting to achieve the same
effect.

*from FOSSwire <http://fosswire.com/post/2009/2/sysctl-swappiness/>*


On Tue, Apr 14, 2009 at 10:17, jaromil <jaromil@???> wrote:

>
>
> hi Ryan,
>
> On Mon, Apr 13, 2009 at 10:02:09AM +0000, ryan wrote:
>
> > Hi, is there a way to change the swappiness variable in dyne, is it
> > relevant?
>
> what do you exactly mean by swappiness ? :)
>
> in case you refer to the time needed to switch between different
> parallel operations, then you have to look into the wonderful world of
> scheduling at kernel level. dyne:bolic 2.5.2 uses the last release of
> Con Kolivas Linux patches for low latency, but still comes with all
> necessary tools and sources to compile your own kernel.
>
> > And also, how would I go about getting dyne to boot into the
> > terminal?
>
> just add the kernel option at boot: ascii=true
>
> this will prevent X from starting.
>
> ciao
>
> - --
>
> jaromil, dyne.org developer, http://jaromil.dyne.org
>
> GPG: 779F E8B5 47C7 3A89 4112 64D0 7B64 3184 B534 0B5E
>
> _______________________________________________
> dyne:bolic GNU/Linux http://dynebolic.org
> open wiki http://lab.dyne.org/DynebolicFaq
>