From a1c2476aefba4a4d422e30e20c04118d201b91f0 Mon Sep 17 00:00:00 2001
From: Peter van Dijk <peter.van.dijk@powerdns.com>
Date: Thu, 20 Jun 2019 10:42:55 +0200
Subject: [PATCH] avoid busy looping on incoming notify storm

---
 pdns/communicator.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pdns/communicator.cc b/pdns/communicator.cc
index 48f481dcf5..d47360eb7e 100644
--- a/pdns/communicator.cc
+++ b/pdns/communicator.cc
@@ -120,7 +120,10 @@ void CommunicatorClass::mainloop(void)
 
         if(rc)
           Utility::sleep(1);
-        else { 
+        else {
+          // eat up extra posts to avoid busy looping if many posts were done
+          while (d_any_sem.tryWait() == 0) {
+          }
           break; // something happened
         }
         // this gets executed at least once every second
-- 
2.47.2