On 11/19/2015 09:23 AM, Christoph Hellwig wrote: > It's pretty much guaranteed a block layer bug, most likely in the > merge bios to request infrastucture where we don't obey the merging > limits properly. > > Does either of you have a known good and first known bad kernel? Well, I have been fighting a similar issue for several months now, albeit with multipath enabled. Haven't had much progress with this, sadly. Seeing that this is our distro kernel it might or might not be related; however, as the symptoms are identical there still is a chance that this is actually a generic block-layer problem. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html