On 05/05/2010 09:52 AM, Stefan Weinhuber wrote: hi, > At the time this change was made we had the problem that the > default scheduler chosen by the distributions resulted in > bad performance for DASD devices. Have you done recently new cfq vs. deadline tests, in z/VM and LPAR ? > I agree that hard coding this choice into the driver is not pretty, > but it is pragmatic. It's awful. Easier and simpler from user space: /sys/block/dasdX/queue/scheduler > Some generic mechanism for setting driver specific > defaults would be nicer, but I doubt that many other drivers would > actually benefit from such an interface. see s390-tools-1.8.4/etc/udev/rules.d/60-readahead.rules That's the way to do it. -thanks- -- «Allá muevan feroz guerra, ciegos reyes por un palmo más de tierra; que yo aquí tengo por mío cuanto abarca el mar bravío, a quien nadie impuso leyes. Y no hay playa, sea cualquiera, ni bandera de esplendor, que no sienta mi derecho y dé pecho a mi valor.» -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
