On Wed, Jul 08, 2015 at 11:03:42AM +0200, Christoph Nelles wrote: > Hi, > > Can the dm-cache writeback cache buffer direct IO or goes direct IO > always immediately to the origin device? Yes, the device mapper layer knows nothing about direct IO vs page cache IO. > I am currently performing tests and see that random direct write IO > never hits the cache, even after overwriting the same region over > and over. Could you try with the latest kernels and the new smq policy please? - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
