On Tue 06-03-07 06:36:09, Ulrich Drepper wrote: > Christoph Hellwig wrote: > > fallocate with the whence argument and flags is already quite complicated, > > I'd rather have another call for placement decisions, that would > > be called on an fd to do placement decissions for any further allocations > > (prealloc, write, etc) > > Yes, posix_fallocate shouldn't be made more complicated. But I don't > understand why requesting linear layout of the blocks should be an > option. It's always an advantage if the blocks requested this way are > linear on disk. So, the kernel should always do its best to make this > happen, without needing an additional option. Actually, it's not that simple. You want linear layout of blocks you are going to read. That is not necessary a linear layout of blocks in a single file - trace sometime a start of some complicated app like KDE. You find it's seeking like a hell because it needs a few blocks from a ton of distinct files (shared libs, config files, etc). As these files are mostly read only, it's advantageous to interleave them on disk or at least keep them close. Honza -- Jan Kara <jack@xxxxxxx> SuSE CR Labs - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
