本文介紹了用于查詢實時統計信息的語句。
SHOW [FULL] STATS
查看整體的統計信息,這些信息都是瞬時值。 注意不同版本的PolarDB-X的SHOW FULL STATS
的結果是有區別的。
示例:
SHOW STATS;
+------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+
| QPS | RDS_QPS | SLOW_QPS | PHYSICAL_SLOW_QPS | ERROR_PER_SECOND | MERGE_QUERY_PER_SECOND | ACTIVE_CONNECTIONS | RT(MS) | RDS_RT(MS) | NET_IN(KB/S) | NET_OUT(KB/S) | THREAD_RUNNING | DDL_JOB_COUNT | BACKFILL_ROWS | CHECKED_ROWS |
+------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+
| 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 1 | 0.00 | 0.00 | 0.00 | 0.00 | 1 | 0 | 0 | 0 |
+------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+
show full stats;
+------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+
| QPS | RDS_QPS | SLOW_QPS | PHYSICAL_SLOW_QPS | ERROR_PER_SECOND | VIOLATION_PER_SECOND | MERGE_QUERY_PER_SECOND | ACTIVE_CONNECTIONS | CONNECTION_CREATE_PER_SECOND | RT(MS) | RDS_RT(MS) | NET_IN(KB/S) | NET_OUT(KB/S) | THREAD_RUNNING | HINT_USED_PER_SECOND | HINT_USED_COUNT | AGGREGATE_QUERY_PER_SECOND | AGGREGATE_QUERY_COUNT | TEMP_TABLE_CREATE_PER_SECOND | TEMP_TABLE_CREATE_COUNT | MULTI_DB_JOIN_PER_SECOND | MULTI_DB_JOIN_COUNT | CPU | FREEMEM | FULLGCCOUNT | FULLGCTIME |
+------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+
| 1.63 | 1.68 | 0.03 | 0.03 | 0.02 | 0.00 | 0.00 | 6 | 0.01 | 157.13 | 51.14 | 134.33 | 1.21 | 1 | 0.00 | 54 | 0.00 | 663 | 0.00 | 512 | 0.00 | 516 | 0.09% | 6.96% | 76446 | 21326906 |
+------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+
1 row in set (0.01 sec)
重要列說明:
- QPS:應用到PolarDB-X的QPS,通常稱為邏輯QPS;
- RDS_QPS:PolarDB-X到RDS的QPS,通常稱為物理QPS;
- ERROR_PER_SECOND:每秒的錯誤數,包含SQL語法錯誤,主鍵沖突,系統錯誤,連通性錯誤等各類錯誤總和;
- VIOLATION_PER_SECOND:每秒的主鍵或者唯一鍵沖突;
- MERGE_QUERY_PER_SECOND:通過分庫分表,從多表中進行的查詢;
- ACTIVE_CONNECTIONS:正在使用的連接;
- CONNECTION_CREATE_PER_SECOND:每秒創建的連接數;
- RT(MS):應用到PolarDB-X的響應時間,通常稱為邏輯RT(響應時間);
- RDS_RT(MS):PolarDB-X到RDS/MySQL的響應時間,通常稱為物理RT;
- NET_IN(KB/S):PolarDB-X收到的網絡流量;
- NET_OUT(KB/S):PolarDB-X輸出的網絡流量;
- THREAD_RUNNING:正在運行的線程數;
- HINT_USED_PER_SECOND:每秒帶HINT的查詢的數量;
- HINT_USED_COUNT:啟動到現在帶HINT的查詢總量;
- AGGREGATE_QUERY_PER_SECOND:每秒聚合查詢的頻次;
- AGGREGATE_QUERY_COUNT:聚合查詢總數(歷史累計數據);
- TEMP_TABLE_CREATE_PER_SECOND:每秒創建的臨時表的數量;
- TEMP_TABLE_CREATE_COUNT:啟動到現在創建的臨時表總數量;
- MULTI_DB_JOIN_PER_SECOND:每秒跨庫JOIN的數量;
- MULTI_DB_JOIN_COUNT:啟動到現在跨庫JOIN的總量。
SHOW DB STATUS
用于查看物理庫容量/性能信息,所有返回值為實時信息。 容量信息通過MySQL系統表獲得,與真實容量情況可能有差異。
示例:
SHOW DB STATUS;
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+
| ID | NAME | CONNECTION_STRING | PHYSICAL_DB | SIZE_IN_MB | RATIO | THREAD_RUNNING |
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+
| 1 | drds_db_1516187088365daui | 100.100.64.1:59077 | TOTAL | 13.109375 | 100% | 3 |
| 2 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0000 | 1.578125 | 12.04% | |
| 3 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0001 | 1.4375 | 10.97% | |
| 4 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0002 | 1.4375 | 10.97% | |
| 5 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0003 | 1.4375 | 10.97% | |
| 6 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0004 | 1.734375 | 13.23% | |
| 7 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0005 | 1.734375 | 13.23% | |
| 8 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0006 | 2.015625 | 15.38% | |
| 9 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0007 | 1.734375 | 13.23% | |
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+
重要列說明:
- NAME:代表一個PolarDB-X DB,此處顯示的是PolarDB-X內部標記,與PolarDB-X DB名稱不同;
- CONNECTION_STRING:分庫的連接信息;
- PHYSICAL_DB:分庫名稱,
TOTAL
行代表一個PolarDB-X DB中所有分庫容量的總和; - SIZE_IN_MB:分庫中數據占用的空間,單位為MB;
- RATIO:單個分庫數據量在當前PolarDB-X DB總數據量中的占比;
- THREAD_RUNNING:物理數據庫實例當前正在執行的線程情況,含義與MySQL語句
SHOW GLOBAL STATUS
返回值的含義相同,詳情請參考 MySQL 文檔。
SHOW TABLE STATUS
獲取表的信息,該指令聚合了底層各個物理分表的數據。
示例:
SHOW TABLE STATUS;
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
| NAME | ENGINE | VERSION | ROW_FORMAT | ROWS | AVG_ROW_LENGTH | DATA_LENGTH | MAX_DATA_LENGTH | INDEX_LENGTH | DATA_FREE | AUTO_INCREMENT | CREATE_TIME | UPDATE_TIME | CHECK_TIME | COLLATION | CHECKSUM | CREATE_OPTIONS | COMMENT |
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
| sbtest1 | InnoDB | 10 | Dynamic | 0 | 0 | 1310720 | 0 | 0 | 0 | 0 | 2021-07-20 15:39:37 | NULL | NULL | utf8mb4_general_ci | NULL | | |
| t1 | InnoDB | 10 | Dynamic | 0 | 0 | 2621440 | 0 | 2621440 | 0 | 200000 | 2021-07-26 20:11:15 | NULL | NULL | utf8mb4_general_ci | NULL | | |
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
重要列詳解:
- NAME:表名稱;
- ENGINE:表的存儲引擎;
- VERSION:表的存儲引擎的版本;
- ROW_FORMAT:行格式,主要是Dynamic、Fixed、Compressed這三種格式。動態(Dynamic)行的行長度可變,例如VARCHAR或BLOB類型字段;固定(Fixed)行是指行長度不變,例如CHAR和INTEGER類型字段;
- ROWS:表中的行數;
- AVG_ROW_LENGTH:平均每行包括的字節數;
- DATA_LENGTH:整個表的數據量(單位:字節);
- MAX_DATA_LENGTH:表可以容納的最大數據量;
- INDEX_LENGTH:索引占用磁盤的空間大小 ;
- CREATE_TIME:表的創建時間;
- UPDATE_TIME:表的最近更新時間;
- COLLATION:表的默認字符集和字符排序規則;
- CREATE_OPTIONS:指表創建時的其他所有選項。
SHOW TABLE INFO [name]
獲取各個分表的數據量信息。
示例:
SHOW TABLE INFO SBTEST1;
+----+--------------+-----------------+------------+
| ID | GROUP_NAME | TABLE_NAME | SIZE_IN_MB |
+----+--------------+-----------------+------------+
| 0 | test1_000000 | sbtest1_wo5k_00 | 0.01562500 |
| 1 | test1_000000 | sbtest1_wo5k_01 | 0.01562500 |
| 2 | test1_000005 | sbtest1_wo5k_10 | 0.01562500 |
| 3 | test1_000005 | sbtest1_wo5k_11 | 0.01562500 |
| 4 | test1_000010 | sbtest1_wo5k_20 | 0.01562500 |
| 5 | test1_000010 | sbtest1_wo5k_21 | 0.01562500 |
| 6 | test1_000015 | sbtest1_wo5k_30 | 0.01562500 |
| 7 | test1_000015 | sbtest1_wo5k_31 | 0.01562500 |
| 8 | test1_000020 | sbtest1_wo5k_40 | 0.01562500 |
| 9 | test1_000020 | sbtest1_wo5k_41 | 0.01562500 |
| 10 | test1_000025 | sbtest1_wo5k_50 | 0.01562500 |
| 11 | test1_000025 | sbtest1_wo5k_51 | 0.01562500 |
| 12 | test1_000030 | sbtest1_wo5k_60 | 0.01562500 |
| 13 | test1_000030 | sbtest1_wo5k_61 | 0.01562500 |
| 14 | test1_000035 | sbtest1_wo5k_70 | 0.01562500 |
| 15 | test1_000035 | sbtest1_wo5k_71 | 0.01562500 |
+----+--------------+-----------------+------------+
重要列詳解:
- ID:標識;
- GROUP_NAME:分庫名;
- TABLE_NAME:物理分表名;
- SIZE_IN_MB:表大小。