Can Sar <csar@xxxxxxxxxxxx> wrote: > the driver just cycles through all devices that make up a soft raid > device and just calls generic_make_request on them. Is this correct, or > does some other function involved in the write process (starting from > the soft raid level down) actually wait on buffers to enforce > restrictions that e.g. cause blocks for one disk to be written before > those of another? None that I know of. Neil may have more to say. In particular, I don't know of any *explicit* mechanism that guarantees that write order is preserved on any ONE mirror (in the case of raid1). On the other hand, md interposes its own make_request (as I recall), so the generic kernel request elevator aggregation algorithm does not apply. And I think I remember that it does not allow queues greater than length 1. If so, that would be helpful. Peter - 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