Hello, On Fri, Jan 14, 2022 at 10:31:55AM +0100, Peter Zijlstra wrote: > So part of the problem I have with this is that these external things > can consume all the bandwidth and basically indefinitely starve the > group. > > This is doulby so if you're going to account things like softirq network > processing. So, anything which is accounted this way should slow down / stall the originator so that backcharges can't run away. In many cases, these connections are already there - e.g. if you keep charging socket rx buffers to a cgroup, the processes in the cgroup will slow down and the backpressure on the network socket will slow down the incoming packets. Sometimes, the backpressure propagation needs to be added explicitly - e.g. filesystem metadata writes can run away because something can keeping on issuing metadata updates without getting throttled neither on memory or io side. So, for situations like that, we need to add an explicit mechanism to throttle the originator asynchronously. Thanks. -- tejun