The shrink_dcache_parent() can take a very long time for deep directory trees: minutes for depth of 100,000, probably hours for depth of 1,000,000. The reason is that after dropping a leaf, it starts again from the root. Filesystems affected include FUSE, NFS, CIFS. Others I haven't checked. NFS and to a lesser extent CIFS don't seem to efficiently handle lookups within such a deep hierarchy, so they're sort of immune. But with FUSE it's pretty easy to DoS the system. Limiting the depth to some sane value could work around this problem, but that would mean having to traverse subtrees in rename(). Any better ideas? Thanks, Miklos - 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
