>> For example, /usr/include/ufs/ffs/fs.h suggests that the super block >> could bein one of 4 different places on your partition, depending on >> what size your disk is, and what version of superblock you're using. > From my memory of the ffs disk layout, fs block/sector numbers start > from the beginning of the partition and just avoid allocating the > area containing the subperblock copies.
Yes. > So the position of the superblocks (one exists in each cylinder > group) is rather irrelevant. Semi-. You want your blocks (and frags, if applicable) to be stripe- and sector-aligned. However, the superblock is block-aligned, at least in FFS versions I've worked with, so if it's aligned properly then all blocks will be too. > What is more likely to cause grief is 512 byte writes - since modern > disks have 4k physical sectors. Indeed. And some of them lie about it, too. :( /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML [email protected] / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
