On Thu, Oct 18, 2012 at 04:24:04PM -0700, Tejun Heo wrote: > Hello, Vivek. > > On Wed, Oct 17, 2012 at 09:49:45AM -0400, Vivek Goyal wrote: > > Can you explain a bit more. Whe do you mean by "total number queued". I > > think throttle.io_queued will total number of bios queued in the cgroup > > at the time of query. > > Instead of exposing the number that blk-throttle currently has > deferred, we can expose the number of bios that have been sent to > blk-throttle and the number of bios which left blk-throttle, both > monotically increasing and the difference indicating the number being > deferred.
Ok, I see it now. So we currently already maintain the number of IOs dispatched from blk-throttle in throttle.io_serviced. Now you are suggesting that maintain another counter which keeps track of total number IOs submitted to blk-throttle, say throttle.io_submitted? I think using throttle.io_queued will be little confusing because in CFQ we already use blkio.io_queued to represent number of IOs currently queued and it is not monotonically increasing value. > That way we can stick to the usual stats facility. So how does this help? Because it is a monotonically increasing value we can use per cpu stats without extra locking? Or somthing else? Thanks Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
