Re: [Devil-linux-develop] thinking about ramdisk size as a function of installed ram

[Heiko Z. <he...@zu...>]

Friedrich Lobenstock wrote:
> On Sat, 23 Mar 2002 09:43, Heiko Zuerker wrote:
> 
> 
>>** parameter in /etc/sysconfig/config:
>>CONFIG_RAMDISK_SIZE=auto | size in MB
>>
>>So you could specify the maximum size manually or use our script to
>>calculate it. Per default it should be set to "auto".
>>
> 
> Hmmm...don't know how to resize a shmfs. There's no option for that.
> Why that, you might ask. The ramdisk get's created and then the config
> disk gets read and extracted into it. But what I could think of is
> that save_config extracts the CONFIG_RAMDISK_SIZE from
> /etc/sysconfig/config and creates a file on the floppy disk eg.
> initrd.conf. BTW with this file we could also tell the linuxrc script
> in the initrd which scsi driver it should load.

Yes you would have to extract the file.
I hope that the Linux file cache is good enough, that he doesn't read 
the tar file again, when we unpack the configuration. Otherwise we would 
have to find a better solution, because it takes to long.
We could also go ahead and copy the tar file into the tmp directory and 
work from there.

CONFIG_INITRD_MODULES="list of modules"
I like that idea, this would be an easy and good solution.

>>** more intelligent
>>The script should also take care about swap space, but should print
>>out a warning when he thinks that the system will start swapping.
>>With this warning, the user would know that he looses performance
>>but the system will still function as expected
>>
> 
> As a start I would just calculate the ramdisk usage of the base system
> and each package, create files PACKAGE-NAME.size with the size value
> in it. So the initrd can calculate when it has to stop extracting
> packages to the ramdisk because the ramdisk would overflow. With this
> method we can leave some space for temp files so the user can at least
> change his config files. Because with a ramdisk that has 0 bytes free
> the user could destroy his config. Happend to me once, so a simple
> passwd command destroyed the /etc/passwd file - not much fun if the
> machine is 250 miles away and if you drop the ssh connection

That's ok, we can't have a 100% solution immediately.
The scripts will be improved over time.

> I would leave this task to a eg. php script on the webpage where the
> user selects what he want's to use and then the script outputs our
> recommendations for his system. (BTW is PHP on www.devil-linux.org
> possible?)

Yes, PHP4 with MySQL

-- 

cu
   Heiko

We are Penguin, Resistance is futile!

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