X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=src%2Ffilter_load_balance.cpp;h=dafe8f3a615a675d38029e3675b476fb5ee0802c;hb=586d78659d671683f33ec55f4a7d32b28e345ccd;hp=64536f2d76713d1e172084ae7b76d6104f424eec;hpb=66d4ec677bbc06aa9be29ab2e5fa2bec7442a7fa;p=metaproxy-moved-to-github.git

diff --git a/src/filter_load_balance.cpp b/src/filter_load_balance.cpp
index 64536f2..dafe8f3 100644
--- a/src/filter_load_balance.cpp
+++ b/src/filter_load_balance.cpp
@@ -1,22 +1,39 @@
-/* $Id: filter_load_balance.cpp,v 1.2 2007-01-03 15:03:55 marc Exp $
-   Copyright (c) 2005-2006, Index Data.
+/* This file is part of Metaproxy.
+   Copyright (C) Index Data
 
-   See the LICENSE file for details
- */
+Metaproxy is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
 
 #include "config.hpp"
-#include "session.hpp"
-#include "package.hpp"
-#include "filter.hpp"
+#include <metaproxy/package.hpp>
+#include <metaproxy/filter.hpp>
 #include "filter_load_balance.hpp"
-#include "util.hpp"
+#include <metaproxy/util.hpp>
+
 
 #include <boost/thread/mutex.hpp>
-#include <boost/date_time/posix_time/posix_time.hpp>
 
+#include <yaz/diagbib1.h>
+#include <yaz/log.h>
 #include <yaz/zgdu.h>
 
-#include <iostream>
+// remove max macro if already defined (defined later in <limits>)
+#ifdef max
+#undef max
+#endif
+
 #include <list>
 #include <map>
 #include <limits>
@@ -24,16 +41,19 @@
 namespace mp = metaproxy_1;
 namespace yf = mp::filter;
 
-namespace metaproxy_1 {
-    namespace filter {
-        class LoadBalance::Impl {
+namespace metaproxy_1
+{
+    namespace filter
+    {
+        class LoadBalance::Impl
+        {
         public:
             Impl();
             ~Impl();
             void process(metaproxy_1::Package & package);
             void configure(const xmlNode * ptr);
         private:
-            // statistic manipulating functions, 
+            // statistic manipulating functions,
             void add_dead(unsigned long session_id);
             //void clear_dead(unsigned long session_id);
             void add_package(unsigned long session_id);
@@ -54,11 +74,6 @@ namespace metaproxy_1 {
                 unsigned int deads;
                 unsigned int cost() {
                     unsigned int c = sessions + packages + deads;
-                    std::cout << "cost  c:" << c 
-                              << " s:" << sessions 
-                              << " p:" << packages 
-                              << " d:" << deads 
-                              <<"\n";
                     return c;
                 }
             };
@@ -72,7 +87,7 @@ namespace metaproxy_1 {
 }
 
 // define Pimpl wrapper forwarding to Impl
- 
+
 yf::LoadBalance::LoadBalance() : m_p(new Impl)
 {
 }
@@ -81,7 +96,8 @@ yf::LoadBalance::~LoadBalance()
 {  // must have a destructor because of boost::scoped_ptr
 }
 
-void yf::LoadBalance::configure(const xmlNode *xmlnode)
+void yf::LoadBalance::configure(const xmlNode *xmlnode, bool test_only,
+                                const char *path)
 {
     m_p->configure(xmlnode);
 }
@@ -92,16 +108,12 @@ void yf::LoadBalance::process(mp::Package &package) const
 }
 
 
-// define Implementation stuff
-
-
-
 yf::LoadBalance::Impl::Impl()
 {
 }
 
 yf::LoadBalance::Impl::~Impl()
-{ 
+{
 }
 
 void yf::LoadBalance::Impl::configure(const xmlNode *xmlnode)
@@ -110,199 +122,238 @@ void yf::LoadBalance::Impl::configure(const xmlNode *xmlnode)
 
 void yf::LoadBalance::Impl::process(mp::Package &package)
 {
-
     bool is_closed_front = false;
 
     // checking for closed front end packages
-    if (package.session().is_closed()){
+    if (package.session().is_closed())
+    {
         is_closed_front = true;
-    }    
+    }
 
     Z_GDU *gdu_req = package.request().get();
 
     // passing anything but z3950 packages
-    if (gdu_req && gdu_req->which == Z_GDU_Z3950){
-
+    if (gdu_req && gdu_req->which == Z_GDU_Z3950)
+    {
         // target selecting only on Z39.50 init request
-        if (gdu_req->u.z3950->which == Z_APDU_initRequest){
+        if (gdu_req->u.z3950->which == Z_APDU_initRequest)
+        {
+            yazpp_1::GDU base_req(gdu_req);
+            Z_APDU *apdu = base_req.get()->u.z3950;
 
+            Z_InitRequest *org_init = base_req.get()->u.z3950->u.initRequest;
             mp::odr odr_en(ODR_ENCODE);
-            Z_InitRequest *org_init = gdu_req->u.z3950->u.initRequest;
 
-            // extracting virtual hosts
             std::list<std::string> vhosts;
-            
             mp::util::remove_vhost_otherinfo(&(org_init->otherInfo), vhosts);
-            
-            // choosing one target according to load-balancing algorithm  
-            
-            if (vhosts.size()){
+            // get lowest of all vhosts.. Remove them if individually if
+            // they turn out to be bad..
+            while (1)
+            {
                 std::string target;
+                std::list<std::string>::iterator ivh = vhosts.begin();
+
+                Package init_pkg(package.session(), package.origin());
+                init_pkg.copy_filter(package);
+
                 unsigned int cost = std::numeric_limits<unsigned int>::max();
-                
-                { //locking scope for local databases
+                {
                     boost::mutex::scoped_lock scoped_lock(m_mutex);
-                    
-                    // load-balancing algorithm goes here
-                    //target = *vhosts.begin();
-                    for(std::list<std::string>::const_iterator ivh 
-                            = vhosts.begin(); 
-                        ivh != vhosts.end();
-                        ivh++){
-                        if ((*ivh).size() != 0){
-                            unsigned int vhcost 
+
+                    for (; ivh != vhosts.end(); )
+                    {
+                        if ((*ivh).size() != 0)
+                        {
+                            unsigned int vhcost
                                 = yf::LoadBalance::Impl::cost(*ivh);
-                            if (cost > vhcost){
+                            yaz_log(YLOG_LOG, "Consider %s cost=%u vhcost=%u",
+                                    (*ivh).c_str(), cost, vhcost);
+                            if (cost > vhcost)
+                            {
                                 cost = vhcost;
                                 target = *ivh;
+                                ivh = vhosts.erase(ivh);
                             }
+                            else
+                                ivh++;
                         }
-                     } 
+                        else
+                            ivh++;
+                    }
+                }
+                if (target.length() == 0)
+                    break;
+                // copying new target into init package
+
+                yazpp_1::GDU init_gdu(base_req);
+                Z_InitRequest *init_req = init_gdu.get()->u.z3950->u.initRequest;
 
-                    // updating local database
+                mp::util::set_vhost_otherinfo(&(init_req->otherInfo),
+                                              odr_en, target, 1);
+
+                init_pkg.request() = init_gdu;
+
+                // moving all package types
+                init_pkg.move();
+
+                // checking for closed back end packages
+                if (!init_pkg.session().is_closed())
+                {
                     add_session(package.session().id(), target);
-                    yf::LoadBalance::Impl::cost(target);
-                    add_package(package.session().id());
+
+                    package.response() = init_pkg.response();
+                    return;
                 }
-                
-                // copying new target into init package
-                mp::util::set_vhost_otherinfo(&(org_init->otherInfo), 
-                                              odr_en, target); 
-                package.request() = gdu_req;
-        }
-            
+            }
+            mp::odr odr;
+            package.response() = odr.create_initResponse(
+                apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
+                "load_balance: no available targets");
+            package.session().close();
+            return;
         }
         // frontend Z39.50 close request is added to statistics and marked
-        else if (gdu_req->u.z3950->which == Z_APDU_close){
+        else if (gdu_req->u.z3950->which == Z_APDU_close)
+        {
             is_closed_front = true;
-            boost::mutex::scoped_lock scoped_lock(m_mutex);        
+            boost::mutex::scoped_lock scoped_lock(m_mutex);
             add_package(package.session().id());
-        }    
+        }
         // any other Z39.50 package is added to statistics
-        else {
-            boost::mutex::scoped_lock scoped_lock(m_mutex);        
+        else
+        {
+            boost::mutex::scoped_lock scoped_lock(m_mutex);
             add_package(package.session().id());
         }
     }
-        
-    // moving all package types 
+
+    // moving all package types
     package.move();
 
+    bool is_closed_back = false;
 
     // 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();
 
     // passing anything but z3950 packages
-    if (gdu_res && gdu_res->which == Z_GDU_Z3950){
-
+    if (gdu_res && gdu_res->which == Z_GDU_Z3950)
+    {
         // session closing only on Z39.50 close response
-        if (gdu_res->u.z3950->which == Z_APDU_close){
+        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 {
+        else
+        {
             boost::mutex::scoped_lock scoped_lock(m_mutex);
             remove_package(package.session().id());
         }
     }
-}
-            
-// getting timestamp for receiving of package
-//boost::posix_time::ptime receive_time
-//    = boost::posix_time::microsec_clock::local_time();
-// //<< receive_time << " "
-// //<< to_iso_string(receive_time) << " "
-//<< to_iso_extended_string(receive_time) << " "
 
+    // finally removing sessions and marking deads
+    if (is_closed_back || is_closed_front)
+    {
+        boost::mutex::scoped_lock scoped_lock(m_mutex);
 
-// statistic manipulating functions, 
-void yf::LoadBalance::Impl::add_dead(unsigned long session_id){
+        // marking backend dead if backend closed without fronted close
+        if (is_closed_front == false)
+            add_dead(package.session().id());
 
-    std::string target = find_session_target(session_id);
+        remove_session(package.session().id());
 
-    std::cout << "add_dead " << session_id << "\n";
-};
+        // making sure that package is closed
+        package.session().close();
+    }
+}
 
-//void yf::LoadBalance::Impl::clear_dead(unsigned long session_id){
-//    std::cout << "clear_dead " << session_id << "\n";
-//};
+// statistic manipulating functions,
+void yf::LoadBalance::Impl::add_dead(unsigned long session_id)
+{
+    std::string target = find_session_target(session_id);
 
-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()
+            && 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::add_package(unsigned long session_id)
+{
     std::string target = find_session_target(session_id);
 
-    if (target.size() != 0){
-        std::map<std::string, TargetStat>::iterator itarg;        
+    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";
         }
     }
-};
+}
 
-void yf::LoadBalance::Impl::remove_package(unsigned long session_id){
+void yf::LoadBalance::Impl::remove_package(unsigned long session_id)
+{
     std::string target = find_session_target(session_id);
 
-    if (target.size() != 0){
-        std::map<std::string, TargetStat>::iterator itarg;        
+    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";
         }
     }
-};
-
-void yf::LoadBalance::Impl::add_session(unsigned long session_id, 
-                                        std::string target){
+}
 
+void yf::LoadBalance::Impl::add_session(unsigned long session_id,
+                                        std::string target)
+{
     // finding and adding session
     std::map<unsigned long, std::string>::iterator isess;
     isess = m_session_target.find(session_id);
-    if (isess == m_session_target.end()){
+    if (isess == m_session_target.end())
+    {
         m_session_target.insert(std::make_pair(session_id, target));
     }
 
     // finding and adding target statistics
     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())
+    {
         TargetStat stat;
         stat.sessions = 1;
+        stat.packages = 0;
+        stat.deads = 0;
         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){
+}
 
+void yf::LoadBalance::Impl::remove_session(unsigned long session_id)
+{
     std::string target;
 
     // finding session
@@ -316,27 +367,25 @@ void yf::LoadBalance::Impl::remove_session(unsigned long session_id){
     // finding target statistics
     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())
+    {
         m_session_target.erase(isess);
         return;
     }
-    
+
     // 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);
     }
-};
-
-std::string 
-yf::LoadBalance::Impl::find_session_target(unsigned long session_id){
+}
 
+std::string yf::LoadBalance::Impl::find_session_target(unsigned long session_id)
+{
     std::string target;
     std::map<unsigned long, std::string>::iterator isess;
     isess = m_session_target.find(session_id);
@@ -347,28 +396,33 @@ yf::LoadBalance::Impl::find_session_target(unsigned long session_id){
 
 
 // cost functions
-unsigned int yf::LoadBalance::Impl::cost(std::string target){
-
-    unsigned int cost;
+unsigned int yf::LoadBalance::Impl::cost(std::string target)
+{
+    unsigned int cost = 0;
 
-    if (target.size() != 0){
-        std::map<std::string, TargetStat>::iterator itarg;        
+    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())
             cost = itarg->second.cost();
-        }
     }
-    
-    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 yf::LoadBalance::Impl::dead(std::string target)
+{
+    unsigned int dead = 0;
 
+    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;
+    }
+    return dead;
+}
 
 
 static mp::filter::Base* filter_creator()
@@ -388,8 +442,9 @@ extern "C" {
 /*
  * Local variables:
  * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
  * indent-tabs-mode: nil
- * c-file-style: "stroustrup"
  * End:
  * vim: shiftwidth=4 tabstop=8 expandtab
  */
+