Merge branch '2.3' into 2.4

maxutils/maxsql/src/mariadb.cc

@@ -13,6 +13,8 @@
 #include <maxsql/mariadb.hh>
 #include <string.h>
 #include <errmsg.h>
+#include <thread>
+#include <chrono>
 #include <maxbase/alloc.h>
 #include <maxbase/assert.h>
 #include <maxbase/format.hh>
@@ -44,6 +46,14 @@ int mysql_query_ex(MYSQL* conn, const std::string& query, int query_retries, tim
     for (int n = 0; rc != 0 && n < query_retries && mysql_is_net_error(mysql_errno(conn))
          && time(NULL) - start < query_retry_timeout; n++)
     {
+        if (n > 0)
+        {
+            // The first reconnection didn't work, wait for one second before attempting again. This
+            // should reduce the likelihood of transient problems causing state changes due to too many
+            // reconnection attemps in a short period of time.
+            std::this_thread::sleep_for(std::chrono::seconds(1));
+        }
+
         rc = mysql_query(conn, query_cstr);
     }