On Sun, 29 April 2007 20:40:42 -0500, Matt Mackall wrote: > > So we should have no trouble checking an exabyte-sized filesystem on a > 4MB box. Even if it has one exabyte-sized file! We check the first > tile, see that it points to our file, then iterate through that file, > checking that the forward and reverse pointers for each block match > and all CRCs match, etc. We cache the file's inode as clean, finish > checking anything else in the first tile, then mark it clean. When we get > to the next tile (and the next billion after that!), we notice that > each block points back to our cached inode and skip rechecking it. How would you catch the case where some block in tile 2 claims to belong to your just-checked inode but the inode has no reference to it? How would you catch the inode referencing the same block twice with just 4MB of memory? I believe you need the fpos field in your rmap for both problems. Jörn -- Anything that can go wrong, will. -- Finagle's Law - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
