OESF Portables Forum

General Forums => General Discussion => Topic started by: ced on May 12, 2004, 03:44:19 am

Title: swap partition
Post by: ced on May 12, 2004, 03:44:19 am

sorry to bring up again a discussion about swap partition...

from this article --] http://hedera.linuxnews.pl/_news/2002/09/0..._long/1445.html (http://hedera.linuxnews.pl/_news/2002/09/03/_long/1445.html)

can we move the partition /home (which is /dev/mtdblock3) to a flash card (SD or CF) and make /dev/mtdblock3 a swap partition?

so finally on the SL5600 (don\'t know about the C-xxx):
  * ~25M for the system (root partition)
  * ~32M of RAM + ~32M of swap = 64M of memory
  * and whatever for the home partition

Title: swap partition
Post by: DrWowe on May 12, 2004, 04:16:33 am

It\'s a bad idea.  You\'re better off using the CF or SD slot for swap.  You can create a swap file on the card of 32 megs or whatever size you want.  At least the flash card can be replaced when it wears out quickly due to overuse...

Or best of all, use a microdrive.

Title: swap partition
Post by: tumnus on May 12, 2004, 04:44:31 am

Is NAND flash memory even supported by the swap filesystem? I didn\'t think it was and probably won\'t be because of the issue DrWowe raised. JFFS2 does write balancing so that no one area of flash gets worn out before another, but even if the swap filesystem did this, I imagine it would write so many times that it would quickly wear the flash out.

Besides which, writing to NAND flash is really slow.

Title: swap partition
Post by: Teletubbie on May 12, 2004, 01:09:45 pm

I heard this would destroy soonly  CF, SD or the intenal jffs2 Flash. Maybe you this according to previos discussions. But maybe newbees cant relocate past discussions and should be aware of installing swap.
Cheers,
Sam

Title: swap partition
Post by: ced on May 13, 2004, 05:08:55 am

anyone has configured NBD? http://nbd.sourceforge.net/ (http://nbd.sourceforge.net/)
if so give a shout...

Title: swap partition
Post by: zbones on May 13, 2004, 05:12:49 pm

Is this any better than putting a swap file on an nfs/samba mounted device?
Also\' it\'s probably not much good for a portable device, unless you have contstantt wifi access (not in the UK  )

Swap device present, move 20 meters,swap device go bye bye, zaurus crashes instantly  

Title: swap partition
Post by: DrWowe on May 13, 2004, 05:17:08 pm

Quote

Is this any better than putting a swap file on an nfs/samba mounted device?

NBD could be more efficient, because its a very simple protocol.  NFS/SMB would add considerable communication overhead.

Might work okay if the device is being used in a fixed location.