On Thu, 2013-03-07 at 09:03 -0800, Linus Torvalds wrote: > On Thu, Mar 7, 2013 at 8:45 AM, Myklebust, Trond > <Trond.Myklebust@xxxxxxxxxx> wrote: > > > > The problem there is that we get into the whole 'hard' vs 'soft' mount > > problem. We're supposed to guarantee data integrity for 'hard' mounts, > > so no funny business is allowed. OTOH, 'soft' mounts time out and return > > EIO to the application anyway, and so shouldn't be a problem. > > > > Perhaps we could add a '-oslushy' mount option :-) that guarantees data > > integrity for all situations _except_ ENETDOWN/ENETUNREACH? > > I do think we are probably over-analyzing this. It's not like people > who want freezing to work usually use flaky NFS. There's really two > main groups: > > - the "freezer as a snapshot mechanism" that might use NFS because > they are in a server environment. > > - the "freeezer for suspend/resume on a laptop" > > The first one does use NFS, and cares about it, and probably would > prefer the freeze event to take longer and finish for all ongoing IO > operations. End result: just ditch the "freezable_schedule()" > entirely. > > The second one is unlikely to really use NFS anyway. End result: > ditching the freezable_schedule() is probably perfectly fine, even if > it would cause suspend failures if the network is being troublesome. > > So for now, why not just replace freezable_schedule() with plain > schedule() in the NFS code, and ignore it until somebody actually > complains about it, and then aim to try to do something more targeted > for that particular complaint? We _have_ had complaints about the laptop suspension problem; that was why Jeff introduced freezable_schedule() in the first place. We've never had complaints about any problems involvinf cgroup_freeze. This is why our focus tends to be on the former, and why I'm more worried about laptop suspend regressions for any short term fixes. -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@xxxxxxxxxx www.netapp.com -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
