raise max_connections default to avoid conflicts with apache max_childs settings (Bug #23883)

sql/mysqld.cc

@@ -5943,9 +5943,11 @@ The minimum value for this variable is 4096.",
    "If there is more than this number of interrupted connections from a host this host will be blocked from further connections.",
    (gptr*) &max_connect_errors, (gptr*) &max_connect_errors, 0, GET_ULONG,
     REQUIRED_ARG, MAX_CONNECT_ERRORS, 1, ~0L, 0, 1, 0},
+  // Default max_connections of 151 is larger than Apache's default max
+  // children, to avoid "too many connections" error in a common setup
   {"max_connections", OPT_MAX_CONNECTIONS,
    "The number of simultaneous clients allowed.", (gptr*) &max_connections,
-   (gptr*) &max_connections, 0, GET_ULONG, REQUIRED_ARG, 100, 1, 16384, 0, 1,
+   (gptr*) &max_connections, 0, GET_ULONG, REQUIRED_ARG, 151, 1, 16384, 0, 1,
    0},
   {"max_delayed_threads", OPT_MAX_DELAYED_THREADS,
    "Don't start more than this number of threads to handle INSERT DELAYED statements. If set to zero, which means INSERT DELAYED is not used.",