On Wed, Apr 4, 2012 at 9:51 AM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote: > On Tue, Apr 03, 2012 at 11:36:55AM -0700, Tejun Heo wrote: > > Hi Tejun, > > Thanks for the RFC and looking into this issue. Few thoughts inline. > > [..] >> IIUC, without cgroup, the current writeback code works more or less >> like this. Throwing in cgroup doesn't really change the fundamental >> design. Instead of a single pipe going down, we just have multiple >> pipes to the same device, each of which should be treated separately. >> Of course, a spinning disk can't be divided that easily and their >> performance characteristics will be inter-dependent, but the place to >> solve that problem is where the problem is, the block layer. > > How do you take care of thorottling IO to NFS case in this model? Current > throttling logic is tied to block device and in case of NFS, there is no > block device. Similarly smb2 gets congestion info (number of "credits") returned from the server on every response - but not sure why congestion control is tied to the block device when this would create problems for network file systems -- Thanks, Steve -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href