On Fri, Apr 01, 2022 at 03:49:19PM +0200, Michal Hocko wrote: > On Thu 31-03-22 10:25:23, Roman Gushchin wrote: > > On Thu, Mar 31, 2022 at 08:41:51AM +0000, Yosry Ahmed wrote: > [...] > > > - A similar per-node interface can also be added to support proactive > > > reclaim and reclaim-based demotion in systems without memcg. > > > > Maybe an option to specify a timeout? That might simplify the userspace part. > > What do you mean by timeout here? Isn't > timeout $N echo $RECLAIM > .... > > enough? It's nice and simple when it's a bash script, but when it's a complex application trying to do the same, it quickly becomes less simple and likely will require a dedicated thread to avoid blocking the main app for too long and a mechanism to unblock it by timer/when the need arises. In my experience using correctly such semi-blocking interfaces (semi- because it's not clearly defined how much time the syscall can take and whether it makes sense to wait longer) is tricky.
