Am Fr, den 26.09.2003 schrieb jon+lvm@silicide.dk um 14:48: > > I don't know, but couldn't the use of a one-sector block slow things > > down because of alignment issues? Perhaps using a 4k block would be more > > useful or storing the sector at the end of the device (like the linux > > raid info sector). > > maybe, but does it matter? You only read the sector once, when you "open" > the device, and write to it when you change password. During use, the real > key is stored in memory, like any other encryption device. No, I meant the following: Let's assume you are using crypto on a raid 0/5 device or something. Usually the filesystem uses 4k blocks. Those blocks would normally never span across two stripes because they are aligned. With a crypto device that uses the first sector now all filesystem blocks get moved by one sector so that there are a lot of blocks that span underlying stripes. A lot of harddisks these days use internal blocks that are larger than 512 bytes so there are also alignment issues. That's why I meant that either this info block should be larger than one sector or it should be moved to the end (and the linux md code does it). -- Christophe Saout <christophe@saout.de> Please avoid sending me Word or PowerPoint attachments. See http://www.fsf.org/philosophy/no-word-attachments.html _______________________________________________ linux-lvm mailing list linux-lvm@sistina.com http://lists.sistina.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
