Added topology argument to dbsim to allow testing master/slave

dbsim/db_params.cpp

@@ -6,6 +6,28 @@
 
 #include <boost/program_options.hpp>
 #include <iostream>
+#include <stdexcept>
+
+namespace
+{
+    void validate_params(const db::params& params)
+    {
+        std::ostringstream os;
+        if (params.n_servers != params.topology.size())
+        {
+            if (params.topology.size() > 0)
+            {
+                os << "Error: --topology=" << params.topology << " does not "
+                   << "match the number of server --servers="
+                   << params.n_servers << "\n";
+            }
+        }
+        if (os.str().size())
+        {
+            throw std::invalid_argument(os.str());
+        }
+    }
+}
 
 db::params db::parse_args(int argc, char** argv)
 {
@@ -22,8 +44,10 @@ db::params db::parse_args(int argc, char** argv)
          "wsrep provider options")
         ("servers", po::value<size_t>(&params.n_servers)->required(),
          "number of servers to start")
+        ("topology", po::value<std::string>(&params.topology),
+         "replication topology (e.g. mm for multi master, ms for master/slave")
         ("clients", po::value<size_t>(&params.n_clients)->required(),
-         "number of clients to start per server")
+         "number of clients to start per master")
         ("transactions", po::value<size_t>(&params.n_transactions),
          "number of transactions run by a client")
         ("rows", po::value<size_t>(&params.n_rows),
@@ -42,5 +66,7 @@ db::params db::parse_args(int argc, char** argv)
         std::cerr << desc << "\n";
         exit(0);
     }
+
+    validate_params(params);
     return params;
 }

dbsim/db_params.hpp

@@ -17,6 +17,7 @@ namespace db
         size_t n_transactions;
         size_t n_rows;
         size_t alg_freq;
+        std::string topology;
         std::string wsrep_provider;
         std::string wsrep_provider_options;
         int debug_log_level;
@@ -27,6 +28,7 @@ namespace db
             , n_transactions(0)
             , n_rows(1000)
             , alg_freq(0)
+            , topology()
             , wsrep_provider()
             , wsrep_provider_options()
             , debug_log_level(0)

dbsim/db_simulator.cpp

@@ -39,10 +39,9 @@ void db::simulator::sst(db::server& server,
 
 std::string db::simulator::stats() const
 {
-    size_t transactions(params_.n_servers * params_.n_clients
-                        * params_.n_transactions);
     auto duration(std::chrono::duration<double>(
                       clients_stop_ - clients_start_).count());
+    long long transactions(stats_.commits + stats_.rollbacks);
     long long bf_aborts(0);
     for (const auto& s : servers_)
     {
@@ -121,10 +120,15 @@ void db::simulator::start()
     // Start client threads
     wsrep::log() << "####################### Starting client load";
     clients_start_ = std::chrono::steady_clock::now();
+    size_t index(0);
     for (auto& i : servers_)
+    {
+        if (params_.topology.size() == 0 || params_.topology[index]  == 'm')
         {
             i.second->start_clients();
         }
+        ++index;
+    }
 }
 
 void db::simulator::stop()

dbsim/dbsim.cpp

@@ -7,6 +7,14 @@
 
 int main(int argc, char** argv)
 {
+    try
+    {
         db::simulator(db::parse_args(argc, argv)).run();
+    }
+    catch (const std::exception& e)
+    {
+        std::cerr << e.what() << std::endl;
+        return 1;
+    }
     return 0;
 }