Neil Brown <neilb@xxxxxxx> wrote: > You can get better speed on creation with > mdadm -C -l6 -n4 -x2 /dev/sd[ab] missing missing /dev/sd[cd] > > i.e. create with 2 missing devices and 2 spares. Recovery onto the > spares will do purely sequential IO on all devices and so will go > much faster. > Doing this requires regenerating datablocks which is more cpu > intensive that generating P and Q, so there might be some CPU > overhead, but the disk throughput is still much faster. > > In 2.6.16, raid6 resync has been improved somewhat. This will not > affect the initial sync, but resync after a crash will only write > P/Q blocks which are wrong and there are usually very few of those. > This means that it will mostly to sequential reads on all drives, so > you get full device speed. Thanks!! -- Sebastian Kuzminsky - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
