Update to periodic purge of expired messages: check the dequeue rate to avoid interfering unnecessarily where the dequeing is sufficient to remove expired messages.

git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@704461 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 48 insertions, 0 deletions

diff --git a/cpp/src/qpid/broker/RateTracker.cpp b/cpp/src/qpid/broker/RateTracker.cpp
new file mode 100644
index 0000000000..5377bcfc0b
--- /dev/null
+++ b/cpp/src/qpid/broker/RateTracker.cpp
@@ -0,0 +1,48 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+#include "RateTracker.h"
+
+using qpid::sys::AbsTime;
+using qpid::sys::Duration;
+using qpid::sys::TIME_SEC;
+
+namespace qpid {
+namespace broker {
+
+RateTracker::RateTracker() : currentCount(0), lastCount(0), lastTime(AbsTime::now()) {}
+
+RateTracker& RateTracker::operator++()
+{
+    ++currentCount;
+    return *this;
+}
+
+double RateTracker::sampleRatePerSecond()
+{
+    int32_t increment = currentCount - lastCount;    
+    AbsTime now = AbsTime::now();
+    Duration interval(lastTime, now);
+    lastCount = currentCount;
+    lastTime = now;
+    return increment ? increment / (interval / TIME_SEC) : 0;
+}
+
+}} // namespace qpid::broker