On Tue, Apr 12, 2011 at 11:49:29AM -0400, Trond Myklebust wrote: > Your approach goes in the direction of further special-casing O_DIRECT > in the NFS client. I'd like to move away from that and towards > integration with the ordinary read/write codepaths so that aside from > adding request coalescing, we can also enable pNFS support. What is the exact plan? Split the direct I/O into two passes, one to lock down the user pages and then a second one to send the pages over the wire, which is shared with the writeback code? If that's the case it should naturally allow plugging in a scheme like Badari to send pages from different iovecs in a single on the wire request - after all page cache pages are non-continuous in virtual and physical memory, too. When do you plan to release your read/write code re-write? If it's not anytime soon how is applying Badari's patch going to hurt? Most of it probably will get reverted with a complete rewrite, but at least the logic to check which direct I/O iovecs can coalesced would stay in the new world order. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
