tencent cloud

All product documents
TDSQL-C for MySQL
DocumentationTDSQL-C for MySQLOperation GuideMonitoring and AlarmsMonitoringSupported Monitoring Metrics
Supported Monitoring Metrics
Download PDF
Last updated: 2024-06-17 16:15:40
Supported Monitoring Metrics
Last updated: 2024-06-17 16:15:40
Download PDF
TDSQL-C for MySQL provides monitoring metrics from both the instance dimension and the database proxy node dimension.

Monitored metrics

Note:
You can view the following monitoring metrics in the console or through TencentCloud API as instructed in Viewing Monitoring Data.
N in the monitoring metric unit indicates the unit of the current query time granularity. For example, if the granularity is 5 seconds, N will be second (sec); if it is 1 minute, N will be minute (min).
Parallel query monitoring metrics are supported only for TDSQL-C for MySQL 8.0 (kernel version 3.1.8) or later.
The monitoring metrics related to columnar indexes are supported by TDSQL-C for MySQL 8.0 kernel version 3.1.14.

Monitoring Metrics at the Instance Dimension

Category
Monitoring Metrics (Chinese)
Monitoring Metrics (English)
Unit
Data Aggregation Method
Resource Monitoring
CPU Utilization
cpu_use_rate
%
MAX
Memory Utilization
memory_use_rate
%
MAX
Memory Usage
memory_use
MB
MAX
Storage Utilization Rate
storage_use_rate
%
MAX
Storage Usage
storage_use
GB
MAX
Data Table Space Usage
data_use
GB
MAX
Temporary Table Space Usage
tmp_use
GB
MAX
Undo Table Space Usage
undo_use
GB
MAX
CCU
CCU
Individual
MAX
Total Client Traffic Sent Per Second
bytes_sent
MB/s
MAX
Total Client Traffic Received Per Second
bytes_received
MB/s
MAX
Read Request IOPS
read_iops
per second
MAX
Write Request IOPS
write_iops
per second
MAX
Total IOPS
iops
per second
MAX
Read I/O Throughput
read_bandwidth
MB/s
MAX
Write I/O Throughput
write_bandwidth
MB/s
MAX
Total I/O Throughput
io_bandwidth
MB/s
MAX
Storage Space Occupied by Log
log_capacity
GB
MAX
Engine Monitoring
Connection
Operations Executed per Second
qps
per second
MAX
Transactions Executed per Second
tps
per second
MAX
Connection Utilization Rate
connection_use_rate
%
MAX
Maximum Number of Connections
max_connections
Individual
MAX
Currently Open Connections
threads_connected
Individual
MAX
Number of Threads Created
threads_created
Individual
SUM
Number of Threads Running
threads_running
Individual
MAX
Access
Slow Queries
slow_queries
Individual
SUM
Full-Table Scans
select_scan
Individual
SUM
Number of Queries
com_select
Individual
SUM
Number of Updates
com_update
Individual
SUM
Number of Deletions
com_delete
Individual
SUM
Number of Insertions
com_insert
Individual
SUM
Number of Overwrite
com_replace
Individual
SUM
Total Number of Requests
queries
Individual
SUM
Number of Submissions
com_commit
Individual
SUM
Number of Rollbacks
com_rollback
Individual
SUM
Number of Full-Table Scan Composite Queries
select_full_join
Individual
SUM
Number of Range Scan Composite Queries
select_full_range_join
Individual
SUM
Number of Sort Merge Passes
sort_merge_passes
Individual
SUM
Qcache Hit Rate
qcache_hit_rate
%
MIN
Qcache Utilization Rate
qcache_use_rate
%
MIN
Number of Multi-Table Updates
com_update_multi
Individual
SUM
Number of Multi-Table Deletions
com_delete_multi
Individual
SUM
Table
Number of Temporary Tables
created_tmp_tables
Individual
SUM
Number of Times Waiting for Table Lock
table_locks_waited
Individual
SUM
Number of Tables Already Opened
opened_tables
Individual
MAX
Number of Table Locks Released Immediately
table_locks_immediate
Individual
SUM
Number of Table Open Cache Hits
table_open_cache_hits
Individual
SUM
Number of Table Open Cache Misses
table_open_cache_misses
Individual
SUM
InnoDB
InnoDB Engine Cache Hit Rate
innodb_cache_hit_rate
%
MIN
InnoDB Engine Cache Utilization
innodb_cache_use_rate
%
MIN
Number of Disk Reads
innodb_os_file_reads
Individual
MAX
Number of Disk Writes
innodb_os_file_writes
Individual
MAX
Number of InnoDB_fsyncs
innodb_os_fsyncs
Individual
MAX
Number of InnoDB Open Tables
innodb_num_open_files
Individual
MAX
Number of InnoDB Reads
innodb_data_read
Byte
SUM
Total Number of InnoDB Reads
innodb_data_reads
Individual
SUM
Total Number of InnoDB Writes
innodb_data_writes
Individual
SUM
Number of InnoDB Writes
innodb_data_written
Byte
SUM
Number of InnoDB Rows Deleted
innodb_rows_deleted
Individual
SUM
Number of InnoDB Rows Inserted
innodb_rows_inserted
Individual
SUM
Number of InnoDB Rows Updated
innodb_rows_updated
Individual
SUM
Number of InnoDB Rows Read
innodb_rows_read
Individual
SUM
Average InnoDB Row Lock Acquiring Time
innodb_row_lock_time_avg
Milliseconds
MAX
Number of InnoDB Row Lock Waits
innodb_row_lock_waits
Individual
SUM
Number of InnoDB Dirty Pages
innodb_buffer_pool_pages_dirty
Individual
MAX
Number of InnoDB Pending Writes
innodb_data_pending_writes
Individual
MAX
Number of InnoDB Pending Reads
innodb_data_pending_reads
Individual
MAX
Number of InnoDB Log Wait Writes
innodb_log_waits
Individual
SUM
Number of InnoDB Log Physical Writes
innodb_log_writes
Individual
SUM
Number of InnoDB Log Physical Write Requests
innodb_log_write_requests
Individual
SUM
Tmp
Number of Temporary Tables
created_tmp_disk_tables
Individual
SUM
Number of Temporary Files
created_tmp_files
Individual
SUM
Handler
Number of Requests to Read Next Line
handler_read_rnd_next
Individual
SUM
Number of Internal Rollbacks
handler_rollback
Individual
SUM
Number of Internal Submissions
handler_commit
Individual
SUM
Buffer
Number of InnoDB Empty Pages
innodb_buffer_pool_pages_free
Individual
MAX
Total Number of InnoDB Pages
innodb_buffer_pool_pages_total
Individual
MAX
Number of InnoDB Logical Reads
innodb_buffer_pool_read_requests
Individual
SUM
Number of InnoDB Physical Reads
innodb_buffer_pool_reads
Individual
SUM
Number of InnoDB Buffer Pool Writes
innodb_buffer_pool_write_request
Individual
SUM
Parallel Query
Number of Parallelly Queried Threads
txsql_parallel_threads_currently_used
Individual
MAX
Number of Failed Parallel Queries
txsql_parallel_stmt_error
Individual
SUM
Number of Executed Parallel Queries
txsql_parallel_stmt_executed
Individual
SUM
Number of Rollback Serial Queries
txsql_parallel_stmt_fallback
Individual
SUM
Column Store Index
Number of Column Store Index Execution Statements
innodb_csi_select_pushdown
Individual
SUM
Number of Column Store Index Rollback Statements
innodb_csi_select_fallback
Individual
SUM
Column Store Index Synchronization Delay
innodb_csi_lag_seconds
Second
MAX
Column Index Storage Usage
innodb_csi_disk_usage
GB
MAX
Number of CSI Creation Failures
innodb_csi_create_failed
Individual
SUM
Other
Total Number of Open Files
open_files
Individual
MAX
Deployment Monitoring
Replication Status
replication_status
0-Yes,1-No
If there is 1, take 1.
Replication Delay
replication_delay
Milliseconds
MAX
Replication Lag in lsn Distance
replication_delay_distance
Bytes
MAX

Monitoring Metrics at Database Proxy Node Dimension

To obtain monitoring metrics at the database proxy node dimension, you need to first enable the database proxy. For detailed metric descriptions, refer to Viewing Database Proxy Monitoring Data.

Performance monitoring data analysis

You can set alarm policies to monitor and analyze performance metrics. Below are some examples:
CPU utilization: It describes how the CPU in the database server is used while running. If the CPU load is high, there will be problems such as slow response of the database system and query delay. Therefore, you can set a threshold alarm for this monitoring metric as needed. Generally, if the CPU utilization exceeds 90%, you need to check the request volume and query performance, and make timely adjustments. If the CPU utilization meets the application or database requirements such as throughput and concurrency and is expected, then it is appropriate.
Used storage space: If the used storage space is always greater than or equal to 85% of the total disk space, you need to check how the storage space is used and whether the data can be deleted from the instance or archived to another system to free up space. If the amount of stored data is too large, the disk is about to be full, and you can solve the problem of insufficient disk space through capacity expansion.
Traffic inbound to/outbound from client: You can check the fluctuations of these metrics in Resource Monitoring to determine whether the problem is caused by the business peak or database, and then optimize the business or adjust the database configuration.
Max connections: max_connections is one of the parameters in TDSQL-C for MySQL, which is used to specify the maximum number of connections allowed by the database. When the database process opens a new connection, the number of currently connected clients will be queried. If the number has reached the set value of max_connections, a new connection cannot be established. If there is a large number of connections, the instance performance drops, and the response time increases, you need to consider restricting the maximum number of connections to the database. If the value of max_connections is set too high, it may cause problems such as insufficient memory and thread crash in the system. Therefore, you should carefully evaluate your application needs and set an appropriate value. The value generally falls between 200 and 500. You can also adjust the maximum number of connections based on the connection conditions of applications and databases.
When a performance metric exceeds the configured alarm threshold, you may need to modify relevant parameters to optimize the database to improve its performance and availability.
Was this page helpful?
You can also Contact Sales or Submit a Ticket for help.
Yes
No

Feedback

Contact Us

Contact our sales team or business advisors to help your business.

Contact Us
Technical Support

Open a ticket if you're looking for further assistance. Our Ticket is 7x24 avaliable.

Submit a Ticket
7x24 Phone Support
Hong Kong, China
+852 800 906 020 (Toll Free)
United States
+1 844 606 0804 (Toll Free)
United Kingdom
+44 808 196 4551 (Toll Free)
Canada
+1 888 605 7930 (Toll Free)
Australia
+61 1300 986 386 (Toll Free)
EdgeOne hotline
+852 300 80699
More local hotlines coming soon