On Sat, Feb 21, 2015 at 12:25:53AM +0900, Akira Hayakawa wrote: > Yes. How big are your log chunks? Presumably they're relatively small (eg, 256k). In which case you can optimise for the common case where you have enough bios to hand to build your log chunk by just referencing the bio payloads, rather than copying. It's only the last bit of io in a burst that should be using this copying slow path. - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel