SERVER-39642 Decrement egress counter when scoped connection not returned to the pool backport

2 files changed, 13 insertions, 4 deletions

diff --git a/src/mongo/client/connpool.cpp b/src/mongo/client/connpool.cpp
index dc2678e655b..b8d49f668e4 100644
--- a/src/mongo/client/connpool.cpp
+++ b/src/mongo/client/connpool.cpp
@@ -336,6 +336,11 @@ void DBConnectionPool::release(const string& host, DBClientBase* c) {
     _pools[PoolKey(host, c->getSoTimeout())].done(this, c);
 }
 
+void DBConnectionPool::decrementEgress(const string& host, DBClientBase* c) {
+    stdx::lock_guard<stdx::mutex> L(_mutex);
+    PoolForHost& p = _pools[PoolKey(host, c->getSoTimeout())];
+    --p._checkedOut;
+}
 
 DBConnectionPool::~DBConnectionPool() {
     // Do not log in destruction, because global connection pools get
@@ -538,6 +543,12 @@ void ScopedDbConnection::done() {
     _conn = NULL;
 }
 
+void ScopedDbConnection::kill() {
+    globalConnPool.decrementEgress(_host, _conn);
+    delete _conn;
+    _conn = NULL;
+}
+
 void ScopedDbConnection::_setSocketTimeout() {
     if (!_conn)
         return;
diff --git a/src/mongo/client/connpool.h b/src/mongo/client/connpool.h
index c3ad2b03a30..a10754c51b2 100644
--- a/src/mongo/client/connpool.h
+++ b/src/mongo/client/connpool.h
@@ -263,6 +263,7 @@ public:
     int getNumBadConns(const std::string& host, double socketTimeout = 0) const;
 
     void release(const std::string& host, DBClientBase* c);
+    void decrementEgress(const std::string& host, DBClientBase* c);
 
     void addHook(DBConnectionHook* hook);  // we take ownership
     void appendConnectionStats(executor::ConnectionPoolStats* stats) const;
@@ -415,10 +416,7 @@ public:
     /** Force closure of the connection.  You should call this if you leave it in
         a bad state.  Destructor will do this too, but it is verbose.
     */
-    void kill() {
-        delete _conn;
-        _conn = 0;
-    }
+    void kill();
 
     /** Call this when you are done with the connection.