On Thu, Oct 22, 2015 at 09:46:12PM +0300, Vladimir Davydov wrote: > On Thu, Oct 22, 2015 at 12:21:31AM -0400, Johannes Weiner wrote: > > The tcp memory controller has extensive provisions for future memory > > accounting interfaces that won't materialize after all. Cut the code > > base down to what's actually used, now and in the likely future. > > > > - There won't be any different protocol counters in the future, so a > > direct sock->sk_memcg linkage is enough. This eliminates a lot of > > callback maze and boilerplate code, and restores most of the socket > > allocation code to pre-tcp_memcontrol state. > > > > - There won't be a tcp control soft limit, so integrating the memcg > > In fact, the code is ready for the "soft" limit (I mean min, pressure, > max tuple), it just lacks a knob. Yeah, but that's not going to materialize if the entire interface for dedicated tcp throttling is considered obsolete. > > @@ -1136,9 +1090,6 @@ static inline bool sk_under_memory_pressure(const struct sock *sk) > > if (!sk->sk_prot->memory_pressure) > > return false; > > > > - if (mem_cgroup_sockets_enabled && sk->sk_cgrp) > > - return !!sk->sk_cgrp->memory_pressure; > > - > > AFAIU, now we won't shrink the window on hitting the limit, i.e. this > patch subtly changes the behavior of the existing knobs, potentially > breaking them. Hm, but there is no grace period in which something meaningful could happen with the window shrinking, is there? Any buffer allocation is still going to fail hard. I don't see how this would change anything in practice. -- 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>