On Tue, Jan 24, 2012 at 10:15:04AM -0500, Chris Mason wrote: > https://lkml.org/lkml/2011/12/13/326 > > This patch is another example, although for a slight different reason. > I really have no idea yet what the right answer is in a generic sense, > but you don't need a 512K request to see higher latencies from merging. That assumes the 512k requests is created by merging. We have enough workloads that create large I/O from the get go, and not splitting them and eventually merging them again would be a big win. E.g. I'm currently looking at a distributed block device which uses internal 4MB chunks, and increasing the maximum request size to that dramatically increases the read performance. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
