On Fri, 2016-01-29 at 17:40 -0500, Tejun Heo wrote: > Hello, > > To implement meaningful IO resource accounting and distribution, it's > necessary to know how much each IO or a group of IOs costs. With > rotational devices, due to the inherent low performance and > concurrency, direct IO cost estimation could be replaced with > provisioning time slices - whatever compositions of IOs which can be > performed in the same amount time are of the same cost. However, > this > approach can no longer be used for modern non-rotational > high-performance devices with high level of concurrency. > > It'd be great to talk about the problem, how to work around the > problem in the near future, and what solutions can be employed in the > long term. Isn't the problem for non-rotational devices pretty similar to the network traffic shaping one? In that model, there's a variety of controllers (hfsc being the most frequently used one) which have realtime (latency), linkshare (minimum bw) and upload (max bw) parameters which we could just copy modulo a few changes. James -- 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
