On Sat, Aug 09, 2008 at 03:23:22AM +0200, Andi Kleen wrote: > > In theory, if the elevator was smart enough, it could actually help > > read seekiness; there are two copies of the metadata, and it shouldn't > > That assumes the elevator actually knows what is nearby? I thought > that wasn't that easy with modern disks with multiple spindles > and invisible remapping, not even talking about RAID > arrays looking like disks. RAID is the big problem, yeah. In general, though, we are already making an assumption in the elevator code and in filesystem code that block numbers which are numerically closer together are "close" from the perspective of disks. There has been talk about trying to make filesystems smarter about allocating blocks by giving them visibility to the RAID parameters; in theory the elevator algorithm could also be made smarter as well using the same information. I'm really not sure if the complexity is worth it, though.... - Ted -- 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
