Hello, Jeff. On Thu, Mar 17, 2016 at 09:32:16PM -0400, Jeff Layton wrote: > > * Are network devices expected to be able to serve as a part of > > storage stack which is depended upon for memory reclamation? > > I think they should be. Cached NFS pages can consume a lot of memory, > and flushing them generally takes network device access. But does that actually work? It's pointless to add WQ_MEM_RECLAIM to workqueues unless all other things are also guaranteed to make forward progress regardless of memory pressure. > > * If so, are all the pieces in place for that to work for all (or at > > least most) network devices? If it's only for a subset of NICs, how > > can one tell whether a given driver needs forward progress guarantee > > or not? > > > > * I assume that wireless drivers aren't and can't be used in this > > fashion. Is that a correction assumption? > > > > People do mount NFS over wireless interfaces. It's not terribly common > though, in my experience. Ditto, I'm very skeptical that this actually works in practice and people expect and depend on it. I don't follow wireless development closely but haven't heard anyone talking about reserving memory pools or people complaining about wireless being the cause of OOM. So, I really want to avoid spraying WQ_MEM_RECLAIM if it doesn't serve actual purposes. It's wasteful, sets bad precedences and confuses future readers. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
