This topic describes the performance metric of PolarDB clusters that are monitored.

## Performance metrics of PolarDB for MySQL clusters

Performance metric | Metric | Data type | Unit | Description |
---|---|---|---|---|

PolarDBDiskUsage | mean_data_size | double | MB | The storage space occupied by the data. |

mean_log_size | double | MB | The storage space occupied by logs. | |

mean_sys_dir_size | double | MB | The storage space occupied by the system. | |

mean_tmp_dir_size | double | MB | The storage space occupied by temporary files. | |

mean_redolog_size | double | MB | The storage space occupied by redo logs. | |

mean_binlog_size | double | MB | The storage space occupied by binary logs. | |

mean_other_log_size | double | MB | The size of other logs. | |

mean_undolog_size | double | MB | The storage space used by undo logs. | |

PolarDBQPSTPS | mean_qps | double | Times | The number of requests per second. |

mean_tps | double | Times | The number of transactions per second. | |

mean_mps | double | Times | The number of operations per second. | |

PolarDBCPU | cpu_ratio | double | Percentage | The CPU utilization (%). |

PolarDBMemory | mem_ratio | double | Percentage | The memory usage (%). |

PolarDBConnections | mean_active_session | double | Count | The number of active connections. |

mean_total_session | double | Count | The total number of current connections. | |

PolarDBNetworkTraffic | mean_input_traffic | double | KB/s | The amount of inbound network traffic per second. |

mean_output_traffic | double | KB/s | The amount of outbound network traffic per second. | |

PolarDBInnoDBBufferRatio | mean_innodb_buffer_dirty_ratio | double | Percentage | The dirty ratio (%) in the buffer pool. |

mean_innodb_buffer_read_hit | double | Percentage | The read hit ratio (%) of the buffer pool. | |

mean_innodb_buffer_use_ratio | double | Percentage | The utilization (%) of the buffer pool. | |

PolarDBInnoDBDataReadWrite | mean_innodb_data_read | double | Byte | The amount of data that is read from the storage engine per second. |

mean_innodb_data_written | double | Byte | The amount of data that is written to the storage engine per second. | |

PolarDBInnoDBBufferRequests | mean_innodb_buffer_pool_read_requests | double | Times | The number of reads from the buffer pool per second. |

mean_innodb_buffer_pool_write_requests | double | Times | The number of writes to the buffer pool per second. | |

PolarDBInnoDBLogWrites | mean_innodb_log_write_requests | double | Times | The number of physical writes to the log per second. |

mean_innodb_os_log_fsyncs | double | Times | The number of synchronizations per second. | |

PolarDBCreatedTempDiskTable | mean_created_tmp_disk_tables | double | Count | The number of temporary tables created per second. |

PolarDBCOMDML | mean_com_delete | double | Count | The number of DELETE statements executed per second. |

mean_com_delete_multi | double | Count | The number of Multi-DELETE statements executed per second. | |

mean_com_insert | double | Count | The number of INSERT statements executed per second. | |

mean_com_insert_select | double | Count | The number of INSERT_SELECT statements executed per second. | |

mean_com_replace | double | Count | The number of REPLACE statements executed per second. | |

mean_com_replace_select | double | Count | The number of REPLACE_SELECT statements executed per second. | |

mean_com_select | double | Count | The number of SELECT statements executed per second. | |

mean_com_update | double | Count | The number of UPDATE statements executed per second. | |

mean_com_update_multi | double | Count | The number of Multi-UPDATE statements executed per second. | |

PolarDBRowDML | mean_innodb_rows_deleted | double | Row | The number of rows deleted per second. |

mean_innodb_rows_inserted | double | Row | The number of rows inserted per second. | |

mean_innodb_rows_read | double | Row | The number of rows read per second. | |

mean_innodb_rows_updated | double | Row | The number of rows updated per second. | |

PolarDBIOSTAT | mean_iops_r | double | Times/second | The read input/output operations per second (IOPS). |

mean_iops_w | double | Times/second | The write IOPS. | |

mean_iops | double | Times/second | The total IOPS. | |

mean_io_throughput_r | double | MB | The read I/O throughput. | |

mean_io_throughput_w | double | MB | The write I/O throughput. | |

mean_io_throughput | double | MB | The total I/O throughput. | |

PolarDBReplicaLag | mean_replication_delay | double | Second | The replication delay. |

## Performance metrics of PolarDB for PostgreSQL and PolarDB-O clusters

Performance metric | Metric | Data type | Unit | Description |
---|---|---|---|---|

PolarDBConnections | mean_total_session | double | Count | The number of current connections. |

mean_active_session | double | Count | The number of current active connections. | |

mean_waiting_connection | double | Count | The number of pending connections. | |

mean_idle_connection | double | Count | The number of idle connections. | |

PolarDBRowDML | mean_tup_returned_delta | double | Row | The number of rows returned per second in the full table scan result. |

mean_tup_fetched_delta | double | Row | The number of rows returned per second in the index scan and secondary index result. | |

mean_tup_inserted_delta | double | Row | The number of rows inserted per second. | |

mean_tup_updated_delta | double | Row | The number of rows updated per second. | |

mean_tup_deleted_delta | double | Row | The number of rows deleted per second | |

PolarDBTransaction | mean_active_transactions | double | Count | The number of active transactions. |

mean_waiting_transactions | double | Count | The number of pending transactions. | |

mean_idle_transactions | double | Count | The number of idle transactions. | |

mean_long_idle_transactions | double | Count | The number of idle long-running transactions. | |

mean_long_transactions | double | Count | The number of long-running transactions. | |

mean_two_pc_transactions | double | Count | The number of XA transactions. | |

mean_long_two_pc_transactions | double | Count | The number of long-running XA transactions. | |

PolarDBQPSTPS | mean_tps | double | Times | The number of transactions per second. |

mean_commits_delta | double | Times | The number of transactions committed per second. | |

mean_rollbacks_delta | double | Times | The number of transactions rolled back per second. | |

mean_deadlocks_delta | double | Times | The number of deadlocks per second. | |

PolarDBBuffer | mean_blks_read_delta | double | Count | The number of block reads per second. |

mean_blks_hit_delta | double | Count | The number of block hits per second. | |

mean_hit_ratio | double | Percentage | The block hit ratio. | |

mean_buffers_clean | double | Count | The cumulative number of buffers written by the background writer during checkpoints. | |

mean_buffers_backend | double | Count | The cumulative number of buffers written by a backend. | |

mean_buffers_backend_fsync | double | Count | The cumulative number of backend fsync calls. | |

mean_buffers_alloc | double | Count | The cumulative number of allocated buffers. | |

PolarDBVacuum | mean_db_age | double | xids | The difference between the current transaction ID and the earliest transaction ID that cannot be recycled. |

PolarDBTemp | mean_temp_files | double | Count | The number of temporary files generated per second. |

mean_temp_bytes | double | Bytes | The amount of temporary file data generated per second. | |

PolarDBCPU | cpu_ratio | double | Percentage | The CPU utilization. |

cpu_user_ratio | double | Percentage | The CPU utilization in the user state. | |

cpu_sys_ratio | double | Percentage | The CPU utilization in the system state. | |

PolarDBMemory | mem_ratio | double | Percentage | The memory usage. |

PolarDBDiskUsage | mean_ins_total_size | double | MB | The used PolarStore space of the instance. |

mean_data_size | double | MB | The used PolarStore space of user data. | |

mean_wal_size | double | MB | The used PolarStore space of Write-Ahead Logging (WAL) logs. | |

mean_tmp_size | double | MB | The used temporary space. | |

mean_log_size | double | MB | The used space of local logs. | |

PolarDBIOSTAT | mean_iops_r | double | Times/second | The read IOPS. |

mean_iops_w | double | Times/second | The write IOPS. | |

mean_iops | double | Times/second | The total IOPS. | |

mean_io_throughput_r | double | MB | The read I/O throughput. | |

mean_io_throughput_w | double | MB | The write I/O throughput. | |

mean_io_throughput | double | MB | The total I/O throughput. |