mysql plugin: Added support for master/slave statistics.

MySQL replication master and slave statistics may be enabled using the newly
added boolean config options "MasterStats" and "SlaveStats". In the first
case, the position in the binlog is collected while in the later case the
read and exec positions in the master log as well as the value of the
Seconds_Behind_Master variable are collected.

For the log positions, the counter type "mysql_log_position" has been
introduced while "time_offset" is used for the Seconds_Behind_Master values.

diff --git a/src/mysql.c b/src/mysql.c
index 5d624a6cc1e255231d47799b737232a77824c13e..2314f230d0dd5020df65bd0fd50d7759daaeb04d 100644 (file)
--- a/src/mysql.c
+++ b/src/mysql.c
@@ -1,6 +1,7 @@
 /**
  * collectd - src/mysql.c
- * Copyright (C) 2006,2007  Florian octo Forster
+ * Copyright (C) 2006-2009  Florian octo Forster
+ * Copyright (C) 2009  Sebastian tokkee Harl
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -17,6 +18,7 @@
  *
  * Authors:
  *   Florian octo Forster <octo at verplant.org>
+ *   Sebastian tokkee Harl <sh at tokkee.org>
  **/
 
 #include "collectd.h"
@@ -43,6 +45,9 @@ struct mysql_database_s /* {{{ */
        char *socket;
        int   port;
 
+       int   master_stats;
+       int   slave_stats;
+
        MYSQL *con;
        int    state;
 };
@@ -127,6 +132,40 @@ static int mysql_config_set_int (int *ret_int, /* {{{ */
        return (0);
 } /* }}} int mysql_config_set_int */
 
+static int mysql_config_set_boolean (int *ret_boolean, /* {{{ */
+                               oconfig_item_t *ci)
+{
+       int status = 0;
+
+       if (ci->values_num != 1)
+               status = -1;
+
+       if (status == 0)
+       {
+               if (ci->values[0].type == OCONFIG_TYPE_BOOLEAN)
+                       *ret_boolean = ci->values[0].value.boolean;
+               else if (ci->values[0].type == OCONFIG_TYPE_STRING)
+               {
+                       if (IS_TRUE (ci->values[0].value.string))
+                               *ret_boolean = 1;
+                       else if (IS_FALSE (ci->values[0].value.string))
+                               *ret_boolean = 0;
+                       else
+                               status = -1;
+               }
+               else
+                       status = -1;
+       }
+
+       if (status != 0)
+       {
+               WARNING ("mysql plugin: The `%s' config option "
+                       "needs exactly one boolean argument.", ci->key);
+               return (-1);
+       }
+       return (0);
+} /* }}} mysql_config_set_boolean */
+
 static int mysql_config (oconfig_item_t *ci) /* {{{ */
 {
        mysql_database_t *db;
@@ -212,6 +251,10 @@ static int mysql_config (oconfig_item_t *ci) /* {{{ */
                else if ((strcasecmp ("Database", child->key) == 0)
                                && (child->children == NULL))
                        status = mysql_config_set_string (&db->database, child);
+               else if (strcasecmp ("MasterStats", child->key) == 0)
+                       status = mysql_config_set_boolean (&db->master_stats, child);
+               else if (strcasecmp ("SlaveStats", child->key) == 0)
+                       status = mysql_config_set_boolean (&db->slave_stats, child);
                else
                {
                        WARNING ("mysql plugin: Option `%s' not allowed here.", child->key);
@@ -367,31 +410,49 @@ static void set_plugin_instance (mysql_database_t *db, value_list_t *vl)
                                sizeof (vl->plugin_instance));
 }
 
-static void counter_submit (const char *type, const char *type_instance,
-               counter_t value, mysql_database_t *db)
+static void submit (const char *type, const char *type_instance,
+               value_t *values, size_t values_len, mysql_database_t *db)
 {
-       value_t values[1];
        value_list_t vl = VALUE_LIST_INIT;
 
-       values[0].counter = value;
+       vl.values     = values;
+       vl.values_len = values_len;
 
-       vl.values = values;
-       vl.values_len = 1;
        set_host (db, &vl);
+
        sstrncpy (vl.plugin, "mysql", sizeof (vl.plugin));
-       sstrncpy (vl.type, type, sizeof (vl.type));
-       sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
        set_plugin_instance (db, &vl);
 
+       sstrncpy (vl.type, type, sizeof (vl.type));
+       if (type_instance != NULL)
+               sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
+
        plugin_dispatch_values (&vl);
+} /* submit */
+
+static void counter_submit (const char *type, const char *type_instance,
+               counter_t value, mysql_database_t *db)
+{
+       value_t values[1];
+
+       values[0].counter = value;
+       submit (type, type_instance, values, STATIC_ARRAY_SIZE (values), db);
 } /* void counter_submit */
 
+static void gauge_submit (const char *type, const char *type_instance,
+               gauge_t value, mysql_database_t *db)
+{
+       value_t values[1];
+
+       values[0].gauge = value;
+       submit (type, type_instance, values, STATIC_ARRAY_SIZE (values), db);
+} /* void gauge_submit */
+
 static void qcache_submit (counter_t hits, counter_t inserts,
                counter_t not_cached, counter_t lowmem_prunes,
                gauge_t queries_in_cache, mysql_database_t *db)
 {
        value_t values[5];
-       value_list_t vl = VALUE_LIST_INIT;
 
        values[0].counter = hits;
        values[1].counter = inserts;
@@ -399,55 +460,163 @@ static void qcache_submit (counter_t hits, counter_t inserts,
        values[3].counter = lowmem_prunes;
        values[4].gauge   = queries_in_cache;
 
-       vl.values = values;
-       vl.values_len = 5;
-       set_host (db, &vl);
-       sstrncpy (vl.plugin, "mysql", sizeof (vl.plugin));
-       sstrncpy (vl.type, "mysql_qcache", sizeof (vl.type));
-       set_plugin_instance (db, &vl);
-
-       plugin_dispatch_values (&vl);
+       submit ("mysql_qcache", NULL, values, STATIC_ARRAY_SIZE (values), db);
 } /* void qcache_submit */
 
 static void threads_submit (gauge_t running, gauge_t connected, gauge_t cached,
                counter_t created, mysql_database_t *db)
 {
        value_t values[4];
-       value_list_t vl = VALUE_LIST_INIT;
 
        values[0].gauge   = running;
        values[1].gauge   = connected;
        values[2].gauge   = cached;
        values[3].counter = created;
 
-       vl.values = values;
-       vl.values_len = 4;
-       set_host (db, &vl);
-       sstrncpy (vl.plugin, "mysql", sizeof (vl.plugin));
-       sstrncpy (vl.type, "mysql_threads", sizeof (vl.type));
-       set_plugin_instance (db, &vl);
-
-       plugin_dispatch_values (&vl);
+       submit ("mysql_threads", NULL, values, STATIC_ARRAY_SIZE (values), db);
 } /* void threads_submit */
 
 static void traffic_submit (counter_t rx, counter_t tx, mysql_database_t *db)
 {
        value_t values[2];
-       value_list_t vl = VALUE_LIST_INIT;
 
        values[0].counter = rx;
        values[1].counter = tx;
 
-       vl.values = values;
-       vl.values_len = 2;
-       set_host (db, &vl);
-       sstrncpy (vl.plugin, "mysql", sizeof (vl.plugin));
-       sstrncpy (vl.type, "mysql_octets", sizeof (vl.type));
-       set_plugin_instance (db, &vl);
-
-       plugin_dispatch_values (&vl);
+       submit ("mysql_octets", NULL, values, STATIC_ARRAY_SIZE (values), db);
 } /* void traffic_submit */
 
+static MYSQL_RES *exec_query (MYSQL *con, const char *query)
+{
+       MYSQL_RES *res;
+
+       int query_len = strlen (query);
+
+       if (mysql_real_query (con, query, query_len))
+       {
+               ERROR ("mysql plugin: Failed to execute query: %s",
+                               mysql_error (con));
+               INFO ("mysql plugin: SQL query was: %s", query);
+               return (NULL);
+       }
+
+       res = mysql_store_result (con);
+       if (res == NULL)
+       {
+               ERROR ("mysql plugin: Failed to store query result: %s",
+                               mysql_error (con));
+               INFO ("mysql plugin: SQL query was: %s", query);
+               return (NULL);
+       }
+
+       return (res);
+} /* exec_query */
+
+static int mysql_read_master_stats (mysql_database_t *db, MYSQL *con)
+{
+       MYSQL_RES *res;
+       MYSQL_ROW  row;
+
+       char *query;
+       int   field_num;
+       unsigned long long position;
+
+       query = "SHOW MASTER STATUS";
+
+       res = exec_query (con, query);
+       if (res == NULL)
+               return (-1);
+
+       row = mysql_fetch_row (res);
+       if (row == NULL)
+       {
+               ERROR ("mysql plugin: Failed to get master statistics: "
+                               "`%s' did not return any rows.", query);
+               return (-1);
+       }
+
+       field_num = mysql_num_fields (res);
+       if (field_num < 2)
+       {
+               ERROR ("mysql plugin: Failed to get master statistics: "
+                               "`%s' returned less than two columns.", query);
+               return (-1);
+       }
+
+       position = atoll (row[1]);
+       counter_submit ("mysql_log_position", "master-bin", position, db);
+
+       row = mysql_fetch_row (res);
+       if (row != NULL)
+               WARNING ("mysql plugin: `%s' returned more than one row - "
+                               "ignoring further results.", query);
+
+       mysql_free_result (res);
+
+       return (0);
+} /* mysql_read_master_stats */
+
+static int mysql_read_slave_stats (mysql_database_t *db, MYSQL *con)
+{
+       MYSQL_RES *res;
+       MYSQL_ROW  row;
+
+       char *query;
+       int   field_num;
+
+       /* WTF? libmysqlclient does not seem to provide any means to
+        * translate a column name to a column index ... :-/ */
+       const int READ_MASTER_LOG_POS_IDX   = 6;
+       const int EXEC_MASTER_LOG_POS_IDX   = 21;
+       const int SECONDS_BEHIND_MASTER_IDX = 32;
+
+       unsigned long long counter;
+       double gauge;
+
+       query = "SHOW SLAVE STATUS";
+
+       res = exec_query (con, query);
+       if (res == NULL)
+               return (-1);
+
+       row = mysql_fetch_row (res);
+       if (row == NULL)
+       {
+               ERROR ("mysql plugin: Failed to get slave statistics: "
+                               "`%s' did not return any rows.", query);
+               return (-1);
+       }
+
+       field_num = mysql_num_fields (res);
+       if (field_num < 33)
+       {
+               ERROR ("mysql plugin: Failed to get slave statistics: "
+                               "`%s' returned less than 33 columns.", query);
+               return (-1);
+       }
+
+       counter = atoll (row[READ_MASTER_LOG_POS_IDX]);
+       counter_submit ("mysql_log_position", "slave-read", counter, db);
+
+       counter = atoll (row[EXEC_MASTER_LOG_POS_IDX]);
+       counter_submit ("mysql_log_position", "slave-exec", counter, db);
+
+       if (row[SECONDS_BEHIND_MASTER_IDX] != NULL)
+       {
+               gauge = atof (row[SECONDS_BEHIND_MASTER_IDX]);
+               gauge_submit ("time_offset", NULL, gauge, db);
+       }
+
+       row = mysql_fetch_row (res);
+       if (row != NULL)
+               WARNING ("mysql plugin: `%s' returned more than one row - "
+                               "ignoring further results.", query);
+
+       mysql_free_result (res);
+
+       return (0);
+} /* mysql_read_slave_stats */
+
 static int mysql_read (user_data_t *ud)
 {
        mysql_database_t *db;
@@ -455,7 +624,6 @@ static int mysql_read (user_data_t *ud)
        MYSQL_RES *res;
        MYSQL_ROW  row;
        char      *query;
-       int        query_len;
        int        field_num;
 
        unsigned long long qcache_hits          = 0ULL;
@@ -488,21 +656,9 @@ static int mysql_read (user_data_t *ud)
        if (mysql_get_server_version (con) >= 50002)
                query = "SHOW GLOBAL STATUS";
 
-       query_len = strlen (query);
-
-       if (mysql_real_query (con, query, query_len))
-       {
-               ERROR ("mysql_real_query failed: %s\n",
-                               mysql_error (con));
-               return (-1);
-       }
-
-       if ((res = mysql_store_result (con)) == NULL)
-       {
-               ERROR ("mysql_store_result failed: %s\n",
-                               mysql_error (con));
+       res = exec_query (con, query);
+       if (res == NULL)
                return (-1);
-       }
 
        field_num = mysql_num_fields (res);
        while ((row = mysql_fetch_row (res)))
@@ -576,6 +732,12 @@ static int mysql_read (user_data_t *ud)
 
        traffic_submit  (traffic_incoming, traffic_outgoing, db);
 
+       if (db->master_stats)
+               mysql_read_master_stats (db, con);
+
+       if (db->slave_stats)
+               mysql_read_slave_stats (db, con);
+
        return (0);
 } /* int mysql_read */
 

diff --git a/src/types.db b/src/types.db
index 05f5f7911ece643ba5a84298125174debd6f55c2..b38c207a66b95a596e7086af6a24f2436609ffca 100644 (file)
--- a/src/types.db
+++ b/src/types.db
@@ -69,6 +69,7 @@ memory                        value:GAUGE:0:281474976710656
 multimeter             value:GAUGE:U:U
 mysql_commands         value:COUNTER:0:U
 mysql_handler          value:COUNTER:0:U
+mysql_log_position     value:COUNTER:0:4294967295
 mysql_octets           rx:COUNTER:0:4294967295, tx:COUNTER:0:4294967295
 mysql_qcache           hits:COUNTER:0:U, inserts:COUNTER:0:U, not_cached:COUNTER:0:U, lowmem_prunes:COUNTER:0:U, queries_in_cache:GAUGE:0:U
 mysql_threads          running:GAUGE:0:U, connected:GAUGE:0:U, cached:GAUGE:0:U, created:COUNTER:0:U