Vivek Goyal wrote: > On Fri, Jul 10, 2009 at 09:56:21AM +0800, Gui Jianfeng wrote: >> Hi Vivek, >> >> This patch exports a cgroup based per group request limits interface. >> and removes the global one. Now we can use this interface to perform >> different request allocation limitation for different groups. >> > > Thanks Gui. Few points come to mind. > > - You seem to be making this as per cgroup limit on all devices. I guess > that different devices in the system can have different settings of > q->nr_requests and hence will probably want different per group limit. > So we might have to make it per cgroup per device limit. Yes, per cgroup per device limitation seems more reasonable. I'll see what i can do. > > - There does not seem to be any checks for making sure that children > cgroups don't have more request descriptors allocated than parent group. Do we really need to make it hierarchical? IMHO, maintaining this limitation for cgroups independently is enough. > > - I am re-thinking that what's the advantage of configuring request > descriptors also through cgroups. It does bring in additional complexity > with it and it should justfiy the advantages. Can you think of some? I'll try, but at least, this feature lets us be able to do more accurate limitation. :) > > Until and unless we can come up with some significant advantages, I will > prefer to continue to use per group limit through q->nr_group_requests > interface instead of cgroup. Once things stablize, we can revisit it and > see how this interface can be improved. I agree. -- Regards Gui Jianfeng -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
