Merge branch '2.3' into 2.4

system-test/open_close_connections.cpp

@@ -0,0 +1,80 @@
+/**
+ * @file open_close_connections.cpp Simple test which creates load which is very short sessions
+ *
+ * - 20 threads are opening and immediatelly closing connection in the loop
+ */
+
+#include <maxtest/testconnections.hh>
+
+#include <atomic>
+#include <vector>
+
+std::atomic<bool> run {true};
+
+void query_thread(TestConnections& test, int thread_id)
+{
+    uint64_t i = 0;
+
+    auto validate = [&](MYSQL* conn){
+                        unsigned int port = 0;
+                        const char* host = "<none>";
+                        mariadb_get_infov(conn, MARIADB_CONNECTION_PORT, &port);
+                        mariadb_get_infov(conn, MARIADB_CONNECTION_HOST, &host);
+
+                        test.expect(mysql_errno(conn) == 0 || errno == EADDRNOTAVAIL,
+                                    "Error opening conn to %s:%u, thread num is %d, iteration %ld, error is: %s\n",
+                                    host, port, thread_id, i, mysql_error(conn));
+
+                        mysql_close(conn);
+                    };
+
+    // Keep running the test until we exhaust all available ports
+    while (run && test.global_result == 0 && errno != EADDRNOTAVAIL)
+    {
+        validate(test.maxscales->open_rwsplit_connection(0));
+        validate(test.maxscales->open_readconn_master_connection(0));
+        validate(test.maxscales->open_readconn_slave_connection(0));
+        i++;
+    }
+}
+
+int main(int argc, char* argv[])
+{
+    TestConnections test(argc, argv);
+
+    // Tuning these kernel parameters removes any system limitations on how many
+    // connections can be created within a short period
+    test.maxscales->ssh_node_f(0,
+                                true,
+                                "sysctl net.ipv4.tcp_tw_reuse=1 net.ipv4.tcp_tw_recycle=1 "
+                                "net.core.somaxconn=10000 net.ipv4.tcp_max_syn_backlog=10000");
+
+    test.repl->execute_query_all_nodes((char*) "set global max_connections = 50000;");
+    test.repl->sync_slaves();
+
+    std::vector<std::thread> threads;
+    constexpr int threads_num = 20;
+
+    for (int i = 0; i < threads_num; i++)
+    {
+        threads.emplace_back(query_thread, std::ref(test), i);
+    }
+
+    constexpr int run_time = 10;
+    test.tprintf("Threads are running for %d seconds", run_time);
+
+    for (int i = 0; i < run_time && test.global_result == 0; i++)
+    {
+        sleep(1);
+    }
+
+    run = false;
+
+    for (auto& a : threads)
+    {
+        a.join();
+    }
+
+    test.check_maxscale_alive(0);
+    return test.global_result;
+}