odd frugal behaviour...

Forum: HD Install
Topic: odd frugal behaviour...
started by: _pathos

Posted by _pathos on Feb. 27 2006,03:40

Laptop A: Dell L400 256mb ram, 256swap, frugal install on hda3
boot options: root=/dev/hda4 quiet vga=791 acpi=off nomce noscsi frugal fromhd=/dev/hda4 norestore nobackup home=hda3

Laptop B: Toshiba 110cs 22mb ram 70mb swap frugal install on hda1
boot options: root=hda1 frugal nousb noapm noscsi nomce noacpi nopci norestore lang=us amp=power-off noideraid nosound nofirewire noapic noapm noagp quiet noeject home=hda2

why are /bin /boot /lib /opt /sbin /usr are links to /ramdisk/* on laptop A
and
/bin /boot /lib /opt /sbin /usr are links to /KNOPPIX/* on laptop B?

lack of memory? boot option?

Posted by mikshaw on Feb. 27 2006,04:09

You probably have one or more *.dsl extensions loading on Laptop A. When you boot a plain frugal DSL, the directories (other than /opt, /home, and /var) are symlinks to KNOPPIX. When you load a myDSL package with a *.dsl filename (or run /etc/init.d/mkwriteable), those symlinks become writeable directories.

It could also be related to the "fromhd" option, but i don't know anything about that.

Posted by _pathos on Feb. 27 2006,07:08

well I never guessed that one

thanks heaps

I don't know what half the options mean but I chuck them in to hopefully reduce cpu/mem usage :/

Posted by _pathos on Feb. 28 2006,01:06

arg its getting errors at boot now...:(

It has messages saying its running out of room on the ramdisk .. whats the minimum size of this? I thinks its at its max of 15mb at the moment.

can I take /home off the ramdisk?

Posted by _pathos on Feb. 28 2006,01:47

ok it isn't the lack of space on the ramdisk.

Laptop A loads far more extentions and only uses 9mb.

Laptop B is crashing during or straight after installing the bc.dsl extention. I've checked the md5 on both laptops and its correct.

As Laptop B is booting it doesn't make any fuss when it adds the symbolic links. Until it crashes installing bc.dsl and claims that /usr/bin/* could not be added and runs a script that tries to use /bin/* (which don't exist).

Is /bin/* linked at the same time as /opt ?

Posted by _pathos on Feb. 28 2006,03:06

Laptop B boots fine with the base option

Ok when I try mydsl-load /cdrom/bc.dsl I get the same errors so its obviously not using the ramdisk properly (/bin still on /knoppix). Could it be automatically using the lowram option?

Posted by _pathos on Feb. 28 2006,03:48

Ok both now have the same boot options...

Yet /bin is still mounted on /KNOPPIX on laptop B....

Is it lack of memory?

Can't you install mydsl extensions from the boot CD?

Posted by _pathos on Feb. 28 2006,04:01

its something to do with /etc/init.d/mkwriteable

it thinks its running out of room on the ramdisk when it building the symbolic links:

cp -srd /KNOPPIX/usr /ramdisk

...blah blah no room on disk...

Posted by cbagger01 on Mar. 01 2006,06:21

Hmm... You have 22MB RAM + 70MB of swap.

That is a fair amount of total space, but maybe you are running out of INodes in your ramdisk like another recent user.

My suspicion is that the RAM+SWAP hack that is used to increase the available size of your ramdisk is somehow not creating enough INodes, but I could be wrong.

I do know that it is difficult to produce enough INodes when trying to load a .dsl file on to a computer that only has 32MB of RAM and no swap.

So until some more light is shed on this one, my advice is to:

1) Only use *.uci or *.tar.gz type extensions on your laptop "B", or

2) Get more RAM for Laptop "B". 64MB is an ideal starting point, but even 40MB is good for small *.dsl extensions.

3) Do a full HD install on Laptop "B" instead of a frugal install.

Posted by _pathos on Mar. 02 2006,05:47

I'm using DSL 2.0

The problem is building the symbollic links to /KNOPPIX/usr

its definitely an INode problem. Is there a limit to them?

Surely 16mb is enough to hold a hundred or two symbollic links?

Posted by cbagger01 on Mar. 02 2006,17:43

The problem, as I understand it, is the creation of the ramdisk file system.

I think there is some internal calculation that gives you "X" number of INodes for every "Y" MB of ramdisk space.

This calculation is not ideal for our needs because the symlinks eat up a lot of INodes even though they don't take up much disk space. I think that calculation was a rule-of-thumb for people who store real files inside the disk, and not a situation where there is a whole lotta symlinking goin' on.

I guess the ideal situation would be to figure out how to manipulate this number and then tweak the linuxrc or other boot script so that it creates more INodes per MB of ramdisk.

But first, we need to understand the ramdisk creation process and the commandline switches that are available to us before the next level of understanding, how to do a "fix", is achieved.

Posted by roberts on Mar. 02 2006,19:29

The number of inodes is controlled via the initial mke2fs command. Either based on number blocks or a pre-calculated fixed number.
If one was building an image for a specific targeted hardware/software configuration then one could adjust these figues to be most accomodating. When I first built appliances, I used several ramdisks each with varying inode formulas but these applicances ran trageted applications so the inode forumla could be fine tuned. DSL is a general pupose micro desktop capable of expanding to quite a large size. Not sure the effort would show results.

Posted by _pathos on Mar. 03 2006,11:16

Surely just the usual calculation + the constant number of INodes needed for the symbollic links should be acceptable?

So theoretically I could find the right file in /etc , modify it and remaster the image?

Thanks for the feedback btw its exceptional.

Posted by cbagger01 on Mar. 05 2006,07:01

From the informatin below,

< http://www.linuxdevcenter.com/linux/cmd/cmd.csp?path=m/mke2fs >

< http://www.die.net/doc/linux/man/man8/mke2fs.8.html >

it appears that there are two ways to tackle the problem during the initial creation of the /ramdisk filesystem.

1) Use the -i switch to change the bytes-per-inode ratio to something better than 4096 bytes for every inode

2) Use the normal inode ratio for most of the time, EXCEPT when ramdisk size < X (where "X" is the magic number where you don't have enough indodes by default). When ramdisk size < X , then either tweak the ratio downward OR set a fixed number of inodes using the -N switch.

I like #2 better because it does not change the behavior (inode ratio) for all users, just the specific ones that need the extra inodes.

You should be able to remaster the change wherever the /ramdisk filesystem is created, either inside the minirt24.gz (linuxrc), or later on in one of the init scripts.

If it is inside the minirt24.gz initial ramdisk, you can make your change without the need for a full blown compressed iso remastering.

Posted by _pathos on Mar. 06 2006,10:22

thanks. I'll give that a go.