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cow persistency again

To answer my own question, in case someone else experiences the same problem:

Using a 2nd /dev/sda2 'casper-rw' partition with an ext2 formatted filesystem 
on the USB stick, even when mounted as /cow with the 'noatime' option, won't 
prevent excessive write cycles to the USB stick for each file read. 

Reason: The Unionfs doesn't respect the 'noatime' option for the /cow branch. 
Hence, I'd not recommend using a 'casper-rw' partition on a USB stick 
for /cow persistency.


On Tuesday 22 May 2007 21:06, neuhoff at mhccorp.com wrote:
> I created a Debian Live for USB-HDD with the current make-live
> 	make-live --bootstrap cdebootstrap -d lenny --username usblive
> --filesystem squashfs -b usb-hdd
> My USB stick has a 2 partitions, one for the Debian live (vfat) and another
> one labeled 'casper-rw' (ext2) for the the persistency. In an attempt to
> reduce the write-cycles to the persistent /cow (mounted from the 'casper-rw
> partition) I also tried to have this 2nd 'casper-rw' partition (/cow)
> mounted with the '-o noatime' option. I changed the following files:
> 	/usr/share/initramfs-tools/scripts/casper
> 	Changed the line
> 	  mount ${cowdevice} -t ${cow_fstype} -o rw /cow || panic "Can not mount
> $cowdevice on /cow"
> 	to
> 	  mount ${cowdevice} -t ${cow_fstype} -o rw,noatime /cow || panic "Can not
> mount $cowdevice on /cow"
> 	Also changed the line
> 	  mount -t unionfs -o dirs=/cow=rw:$rofsstring unionfs "$rootmnt" ||
> panic "Unionfs mount failed"
> 	to
> 	  mount -t unionfs -o noatime,dirs=/cow=rw:$rofsstring unionfs "$rootmnt"
> || panic "Unionfs mount failed"
> However, it seems that it is not mounted with the 'noatime' option. How can
> I accompish this?
> J.Neuhoff
> _______________________________________________
> Debian-live-devel mailing list
> Debian-live-devel at lists.alioth.debian.org
> http://lists.alioth.debian.org/mailman/listinfo/debian-live-devel

	J.Neuhoff - mhccorp.com

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