counting dead connections correctly

[metaproxy-moved-to-github.git] / src / filter_load_balance.cpp

diff --git a/src/filter_load_balance.cpp b/src/filter_load_balance.cpp
index 64536f2..3783ee1 100644 (file)
--- a/src/filter_load_balance.cpp
+++ b/src/filter_load_balance.cpp
@@ -1,4 +1,4 @@
-/* $Id: filter_load_balance.cpp,v 1.2 2007-01-03 15:03:55 marc Exp $
+/* $Id: filter_load_balance.cpp,v 1.4 2007-01-04 13:03:17 marc Exp $
    Copyright (c) 2005-2006, Index Data.
 
    See the LICENSE file for details
@@ -54,7 +54,7 @@ namespace metaproxy_1 {
                 unsigned int deads;
                 unsigned int cost() {
                     unsigned int c = sessions + packages + deads;
-                    std::cout << "cost  c:" << c 
+                    std::cout << "stats  c:" << c 
                               << " s:" << sessions 
                               << " p:" << packages 
                               << " d:" << deads 
@@ -112,6 +112,7 @@ void yf::LoadBalance::Impl::process(mp::Package &package)
 {
 
     bool is_closed_front = false;
+    bool is_closed_back = false;
 
     // checking for closed front end packages
     if (package.session().is_closed()){
@@ -190,15 +191,8 @@ void yf::LoadBalance::Impl::process(mp::Package &package)
 
 
     // checking for closed back end packages
-    if (package.session().is_closed()) {
-        boost::mutex::scoped_lock scoped_lock(m_mutex);
-
-        // marking backend dead if backend closed without fronted close 
-        if (is_closed_front == false)
-            add_dead(package.session().id());
-
-        remove_session(package.session().id());
-    }
+    if (package.session().is_closed())
+        is_closed_back = true;
 
     Z_GDU *gdu_res = package.response().get();
 
@@ -207,14 +201,9 @@ void yf::LoadBalance::Impl::process(mp::Package &package)
 
         // session closing only on Z39.50 close response
         if (gdu_res->u.z3950->which == Z_APDU_close){
+            is_closed_back = true;
             boost::mutex::scoped_lock scoped_lock(m_mutex);
             remove_package(package.session().id());
-            
-            // marking backend dead if backend closed without fronted close 
-            if (is_closed_front == false)
-                add_dead(package.session().id());
-            
-            //remove_session(package.session().id());
         } 
         // any other Z39.50 package is removed from statistics
         else {
@@ -222,6 +211,20 @@ void yf::LoadBalance::Impl::process(mp::Package &package)
             remove_package(package.session().id());
         }
     }
+
+    // finally removing sessions and marking deads
+    if (is_closed_back || is_closed_front){        
+        boost::mutex::scoped_lock scoped_lock(m_mutex);
+
+        // marking backend dead if backend closed without fronted close 
+        if (is_closed_front == false)
+            add_dead(package.session().id());
+
+        remove_session(package.session().id());
+
+        // making sure that package is closed
+        package.session().close();
+    }
 }
             
 // getting timestamp for receiving of package
@@ -235,9 +238,19 @@ void yf::LoadBalance::Impl::process(mp::Package &package)
 // statistic manipulating functions, 
 void yf::LoadBalance::Impl::add_dead(unsigned long session_id){
 
+    
     std::string target = find_session_target(session_id);
 
-    std::cout << "add_dead " << session_id << "\n";
+    if (target.size() != 0){
+        std::map<std::string, TargetStat>::iterator itarg;        
+        itarg = m_target_stat.find(target);
+        if (itarg != m_target_stat.end()
+            && itarg->second.deads < std::numeric_limits<unsigned int>::max()){
+            itarg->second.deads += 1;
+            std::cout << "add_dead " << session_id << " " << target 
+                      << " d:" << itarg->second.deads << "\n";
+        }
+    }
 };
 
 //void yf::LoadBalance::Impl::clear_dead(unsigned long session_id){
@@ -251,7 +264,9 @@ void yf::LoadBalance::Impl::add_package(unsigned long session_id){
     if (target.size() != 0){
         std::map<std::string, TargetStat>::iterator itarg;        
         itarg = m_target_stat.find(target);
-        if (itarg != m_target_stat.end()){
+        if (itarg != m_target_stat.end()
+            && itarg->second.packages 
+               < std::numeric_limits<unsigned int>::max()){
             itarg->second.packages += 1;
             std::cout << "add_package " << session_id << " " << target 
                       << " p:" << itarg->second.packages << "\n";
@@ -265,7 +280,8 @@ void yf::LoadBalance::Impl::remove_package(unsigned long session_id){
     if (target.size() != 0){
         std::map<std::string, TargetStat>::iterator itarg;        
         itarg = m_target_stat.find(target);
-        if (itarg != m_target_stat.end()){
+        if (itarg != m_target_stat.end()
+            && itarg->second.packages > 0){
             itarg->second.packages -= 1;
             std::cout << "remove_package " << session_id << " " << target 
                       << " p:" << itarg->second.packages << "\n";
@@ -289,16 +305,18 @@ void yf::LoadBalance::Impl::add_session(unsigned long session_id,
     if (itarg == m_target_stat.end()){
         TargetStat stat;
         stat.sessions = 1;
-        m_target_stat.insert(std::make_pair(target, stat));
+        stat.packages = 0;  // no idea why the defaut constructor TargetStat()
+        stat.deads = 0;     // is not initializig this correctly to zero ??
+       m_target_stat.insert(std::make_pair(target, stat));
         std::cout << "add_session " << session_id << " " << target 
                   << " s:1\n";
-    } else {
+    } 
+    else if (itarg->second.sessions < std::numeric_limits<unsigned int>::max())
+    {
         itarg->second.sessions += 1;
         std::cout << "add_session " << session_id << " " << target 
                   << " s:" << itarg->second.sessions << "\n";
     }
-    
-    
 };
 
 void yf::LoadBalance::Impl::remove_session(unsigned long session_id){
@@ -322,13 +340,14 @@ void yf::LoadBalance::Impl::remove_session(unsigned long session_id){
     }
     
     // counting session down
-    itarg->second.sessions -= 1;
+    if (itarg->second.sessions > 0)
+        itarg->second.sessions -= 1;
 
     std::cout << "remove_session " << session_id << " " << target 
               << " s:" << itarg->second.sessions << "\n";
     
     // clearing empty sessions and targets
-    if (itarg->second.sessions == 0){
+    if (itarg->second.sessions == 0 && itarg->second.deads == 0 ){
         m_target_stat.erase(itarg);
         m_session_target.erase(isess);
     }
@@ -359,13 +378,24 @@ unsigned int yf::LoadBalance::Impl::cost(std::string target){
         }
     }
     
-    std::cout << "cost " << target << " c:" << cost << "\n";
+    //std::cout << "cost " << target << " c:" << cost << "\n";
     return cost;
 };
 
 unsigned int yf::LoadBalance::Impl::dead(std::string target){
-    std::cout << "dead " << target << "\n";
-    return 0;
+
+    unsigned int dead;
+
+    if (target.size() != 0){
+        std::map<std::string, TargetStat>::iterator itarg;        
+        itarg = m_target_stat.find(target);
+        if (itarg != m_target_stat.end()){
+            dead = itarg->second.deads;
+        }
+    }
+    
+    //std::cout << "dead " << target << " d:" << dead << "\n";
+    return dead;
 };