On Thu, 15 Jan 2009, James Bottomley wrote: > > OK, so they could be calculated on the fly in the elevators, I suppose. > But what would the value be? Right now we use the nonrotational flag to > basically not bother with plugging (no point if no seek penalty) on > certain events where we'd previously have waited for other I/O to join. > But that's really a seek penalty parameter rather than the idea of read > or write costing (although the elevators usually track these dynamically > anyway ... as part of the latency calculations but not explicitly). ... not bother with plugging (no point if no seek penalty) ... I thought there was considerable advantage to plugging writes (in case they turn out to be adjacent) on current and older generations of non-rotational storage? Hugh -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
