From: Johannes Weiner <hannes@xxxxxxxxxxx> Date: Tue, 24 Nov 2015 16:59:40 -0500 > Let the networking stack know when a memcg is under reclaim pressure > so that it can clamp its transmit windows accordingly. > > Whenever the reclaim efficiency of a cgroup's LRU lists drops low > enough for a MEDIUM or HIGH vmpressure event to occur, assert a > pressure state in the socket and tcp memory code that tells it to curb > consumption growth from sockets associated with said control group. > > Traditionally, vmpressure reports for the entire subtree of a memcg > under pressure, which drops useful information on the individual > groups reclaimed. However, it's too late to change the userinterface, > so add a second reporting mode that reports on the level of reclaim > instead of at the level of pressure, and use that report for sockets. > > vmpressure events are naturally edge triggered, so for hysteresis > assert socket pressure for a second to allow for subsequent vmpressure > events to occur before letting the socket code return to normal. > > This will likely need finetuning for a wider variety of workloads, but > for now stick to the vmpressure presets and keep hysteresis simple. > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Acked-by: David S. Miller <davem@xxxxxxxxxxxxx> -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>