From 66693d68462a389a692d1f14a8f31ba071ffbe3c Mon Sep 17 00:00:00 2001
From: Zaiming Shi <zmstone@gmail.com>
Date: Mon, 29 Mar 2021 10:57:37 +0200
Subject: [PATCH] fix(emqx_connection): connection OOM kill immediately

Prior to this change, connection process' OOM kill is a loopback
message, which results in a delayed kill when message queue length
is large.
In this change, the loopback message is changed to an exit signal.
---
 src/emqx_connection.erl | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/emqx_connection.erl b/src/emqx_connection.erl
index 88a1ba4d7..28ea67bf8 100644
--- a/src/emqx_connection.erl
+++ b/src/emqx_connection.erl
@@ -684,9 +684,11 @@ check_oom(State = #state{channel = Channel}) ->
     Zone = emqx_channel:info(zone, Channel),
     OomPolicy = emqx_zone:oom_policy(Zone),
     case ?ENABLED(OomPolicy) andalso emqx_misc:check_oom(OomPolicy) of
-        Shutdown = {shutdown, _Reason} ->
-            erlang:send(self(), Shutdown);
-        _Other -> ok
+        {shutdown, Reason} ->
+            %% triggers terminate/2 callback immediately
+            erlang:exit({shutdown, Reason});
+        _Other ->
+            ok
     end,
     State.