35.4.3 Server Metrics

Skip to Main Content

MySQL 8.4 Reference Manual Including MySQL NDB Cluster 8.4

35.4.3 Server Metrics

The following server metrics are registered by default:

The maximum number of metric instruments which can be created is set by performance_schema_max_metric_classes.

mysql.stats Metrics

Table 35.3 mysql.stats Metrics

Name Source Variable OTEL Type Description
aborted_clients Aborted_clients ASYNC COUNTER The number of connections that were aborted because the client died without closing the connection properly
aborted_connects Aborted_connects ASYNC COUNTER The number of failed attempts to connect to the MySQL server
acl_cache_items_count Acl_cache_items_count ASYNC GAUGE COUNTER The number of cached privilege objects
binlog_cache.disk_use Binlog_cache_disk_use ASYNC COUNTER The number of transactions that used the temporary binary log cache but that exceeded the value of binlog_cache_size and used a temporary file to store statements from the transaction
binlog_cache.use Binlog_cache_use ASYNC COUNTER The number of transactions that used the binary log cache.
binlog_stmt_cache_disk_use Binlog_stmt_cache_disk_use ASYNC COUNTER The number of nontransaction statements that used the binary log statement cache but that exceeded the value of binlog_stmt_cache_size and used a temporary file to store those statements.
binlog_stmt_cache_use Binlog_stmt_cache_use ASYNC COUNTER The number of nontransactional statements that used the binary log statement cache
bytes_received Bytes_received ASYNC COUNTER The number of bytes received from all clients
bytes_sent Bytes_sent ASYNC COUNTER The number of bytes sent to all clients
created.tmp_disk_tables Created_tmp_disk_tables ASYNC COUNTER The number of internal on-disk temporary tables created by the server while executing statements
created.tmp_files Created_tmp_files ASYNC COUNTER How many temporary files mysqld has created
created.tmp_tables Created_tmp_tables ASYNC COUNTER The number of internal temporary tables created by the server while executing statements
error_log.buffered_bytes Error_log_buffered_bytes ASYNC GAUGE COUNTER The number of bytes currently used in the Performance Schema error_log table
error_log.buffered_events Error_log_buffered_events ASYNC GAUGE COUNTER The number of events currently present in the Performance Schema error_log table
error_log.expired_events Error_log_expired_events ASYNC COUNTER The number of events discarded from the Performance Schema error_log table to make room for new events
flush_commands Flush_commands ASYNC COUNTER The number of times the server flushes tables
global_connection_memory Global_connection_memory ASYNC GAUGE COUNTER The memory used by all user connections to the server
locked_connects Locked_connects ASYNC COUNTER The number of attempts to connect to locked user accounts
max_execution_time_exceeded Max_execution_time_exceeded ASYNC COUNTER The number of SELECT statements for which the execution timeout was exceeded
max_execution_time_set Max_execution_time_set ASYNC COUNTER The number of SELECT statements for which a nonzero execution timeout was set
max_execution_time_set_failed Max_execution_time_set_failed ASYNC COUNTER The number of SELECT statements for which the attempt to set an execution timeout failed
max_used_connections Max_used_connections ASYNC GAUGE COUNTER The maximum number of connections that have been in use simultaneously since the server started
ongoing_anonymous_transaction_count Ongoing_anonymous_transaction_count ASYNC GAUGE COUNTER Shows the number of ongoing transactions which have been marked as anonymous
open_files Open_files ASYNC COUNTER The number of files that are open. This count includes regular files opened by the server.
open_streams Open_streams ASYNC COUNTER The number of streams that are open, used mainly for logging
open_table_definitions Open_table_definitions ASYNC GAUGE COUNTER The number of cached table definitions
open_tables Open_tables ASYNC GAUGE COUNTER The number of tables that are open.
opened_files Opened_files ASYNC COUNTER The number of files that have been opened with my_open().
opened_table_definitions Opened_table_definitions ASYNC GAUGE COUNTER The number of table definitions that have been cached.
opened_tables Opened_tables ASYNC COUNTER The number of tables that have been opened
prepared_stmt_count Prepared_stmt_count ASYNC GAUGE COUNTER The current number of prepared statements
queries Queries ASYNC COUNTER The number of statements executed by the server, including ones executed within stored programs. It does not count COM_PING or COM_STATISTICS commands.
questions Questions ASYNC COUNTER The number of statements executed by the server. This includes only statements sent to the server by clients and not statements executed within stored programs.
replica_open_temp_tables Replica_open_temp_tables ASYNC GAUGE COUNTER Number of temporary tables that the replication SQL thread currently has open.
secondary_engine_execution_count Secondary_engine_execution_count ASYNC COUNTER The number of queries offloaded to a secondary engine
select_full_join Select_full_join ASYNC COUNTER The number of joins that perform table scans because they do not use indexes
select_full_range_join Select_full_range_join ASYNC COUNTER The number of joins that used a range search on a reference table
select_range Select_range ASYNC COUNTER The number of joins that used ranges on the first table
select_range_check Select_range_check ASYNC COUNTER The number of joins without keys that check for key usage after each row
select_scan Select_scan ASYNC COUNTER The number of joins that did a full scan of the first table
slow_launch_threads Slow_launch_threads ASYNC COUNTER The number of threads that have taken more than slow_launch_time seconds to create.
slow_queries Slow_queries ASYNC COUNTER The number of queries that have taken more than long_query_time seconds
sort_merge_passes Sort_merge_passes ASYNC COUNTER The number of merge passes that the sort algorithm has had to do
sort_range Sort_range ASYNC COUNTER The number of sorts that were done using ranges
sort_rows Sort_rows ASYNC COUNTER The number of sorted rows.
sort_scan Sort_scan ASYNC COUNTER The number of sorts that were done by scanning the table.
table_locks_immediate Table_locks_immediate ASYNC COUNTER The number of times that a request for a table lock could be granted immediately
table_locks_waited Table_locks_waited ASYNC COUNTER The number of times that a request for a table lock could not be granted immediately and a wait was needed.
table_open_cache_hits Table_open_cache_hits ASYNC COUNTER The number of hits for open tables cache lookups.
table_open_cache_misses Table_open_cache_misses ASYNC COUNTER The number of misses for open tables cache lookups.
table_open_cache_overflows Table_open_cache_overflows ASYNC COUNTER The number of overflows for the open tables cache.
tc_log_page_waits Tc_log_page_waits ASYNC COUNTER For the memory-mapped implementation of the recovery log, this variable increments each time the server was not able to commit a transaction and had to wait for a free page in the log.
threads_cached Threads_cached ASYNC GAUGE COUNTER The number of threads in the thread cache.
threads_connected Threads_connected ASYNC GAUGE COUNTER The number of currently open connections
threads_created Threads_created ASYNC GAUGE COUNTER The number of threads created to handle connections.
threads_running Threads_running ASYNC GAUGE COUNTER The number of threads that are not sleeping.
uptime Uptime ASYNC COUNTER The number of seconds that the server has been up.

mysql.stats.com Metrics

The mysql.stats.com metrics correspond to the Com_xxx statement counter variables. See Section 7.1.10, “Server Status Variables” and Com_xxxfor more information.

The mysql.stats.com metrics are named for those variables, without the Com_ prefix. For example, the select metric corresponds to the Com_select statement counter variable.

These metrics are of OTEL Type ASYNC COUNTER and record the number of times (INTEGER) the corresponding command statement has been executed.

mysql.stats.connection Metrics

The mysql.stats.connection metrics correspond to the Connections and Connection_XXX status variables.

Table 35.4 mysql.stats.connection Metrics

Name Source Variable OTEL Type Description
total Connections ASYNC COUNTER Cumulative count of total connections created.
errors_accept Connection_errors_accept ASYNC COUNTER The number of errors that occurred during calls to accept() on the listening port.
errors_internal Connection_errors_internal ASYNC COUNTER The number of connections refused due to internal errors in the server, such as failure to start a new thread or an out-of-memory condition.
errors_max_connections Connection_errors_max_connections ASYNC COUNTER The number of connections refused because the server max_connections limit was reached.
errors_peer_address Connection_errors_peer_address ASYNC COUNTER The number of errors that occurred while searching for connecting client IP addresses.
errors_select Connection_errors_select ASYNC COUNTER The number of errors that occurred during calls to select() or poll() on the listening port.
errors_tcpwrap Connection_errors_tcpwrap ASYNC COUNTER The number of connections refused by the libwrap library.

mysql.perf_schema Metrics

The mysql.perf_schema correspond to the Performance_schema_XXX status variables. See Section 29.7, “Performance Schema Status Monitoring”.

Table 35.5 mysql.perf_schema Metrics

Name Source Variable OTEL Type Description
accounts_lost Performance_schema_accounts_lost ASYNC COUNTER The number of times a row could not be added to the accounts table because it was full.
cond_classes_lost Performance_schema_cond_classes_lost ASYNC COUNTER How many condition instruments could not be loaded.
cond_instances_lost Performance_schema_cond_instances_lost ASYNC COUNTER How many condition instrument instances could not be created.
digest_lost Performance_schema_digest_lost ASYNC COUNTER The number of digest instances that could not be instrumented in the events_statements_summary_by_digest table.
file_classes_lost Performance_schema_file_classes_lost ASYNC COUNTER How many file instruments could not be loaded.
file_handles_lost Performance_schema_file_handles_lost ASYNC COUNTER How many file instrument instances could not be opened.
file_instances_lost Performance_schema_file_instances_lost ASYNC COUNTER How many file instrument instances could not be created.
hosts_lost Performance_schema_hosts_lost ASYNC COUNTER The number of times a row could not be added to the hosts table because it was full.
index_stat_lost Performance_schema_index_stat_lost ASYNC COUNTER The number of indexes for which statistics were lost.
locker_lost Performance_schema_locker_lost ASYNC COUNTER How many events are lost or not recorded.
memory_classes_lost Performance_schema_memory_classes_lost ASYNC COUNTER The number of times a memory instrument could not be loaded.
metadata_lock_lost Performance_schema_metadata_lock_lost ASYNC COUNTER The number of metadata locks that could not be instrumented in the metadata_locks table.
meter_lost Performance_schema_meter_lost ASYNC COUNTER How many meter instruments could not be loaded.
metric_lost Performance_schema_metric_lost ASYNC COUNTER How many metric instruments could not be loaded.
mutex_classes_lost Performance_schema_mutex_classes_lost ASYNC COUNTER How many mutex instruments could not be loaded.
mutex_instances_lost Performance_schema_mutex_instances_lost ASYNC COUNTER How many mutex instrument instances could not be created.
nested_statement_lost Performance_schema_nested_statement_lost ASYNC COUNTER The number of stored program statements for which statistics were lost.
prepared_statements_lost Performance_schema_prepared_statements_lost ASYNC COUNTER The number of prepared statements that could not be instrumented in the prepared_statements_instances table.
program_lost Performance_schema_program_lost ASYNC COUNTER The number of stored programs for which statistics were lost.
rwlock_classes_lost Performance_schema_rwlock_classes_lost ASYNC COUNTER How many rwlock instruments could not be loaded.
rwlock_instances_lost Performance_schema_rwlock_instances_lost ASYNC COUNTER How many rwlock instrument instances could not be created.
session_connect_attrs_longest_seen Performance_schema_session_connect_attrs_longest_seen ASYNC COUNTER Longest seen connection attribute received.
session_connect_attrs_lost Performance_schema_session_connect_attrs_lost ASYNC COUNTER The number of connections for which connection attribute truncation has occurred
socket_classes_lost Performance_schema_socket_classes_lost ASYNC COUNTER How many socket instruments could not be loaded.
socket_instances_lost Performance_schema_socket_instances_lost ASYNC COUNTER How many socket instrument instances could not be created.
stage_classes_lost Performance_schema_stage_classes_lost ASYNC COUNTER How many stage instruments could not be loaded.
statement_classes_lost Performance_schema_statement_classes_lost ASYNC COUNTER How many statement instruments could not be loaded.
table_handles_lost Performance_schema_table_handles_lost ASYNC COUNTER How many table instrument instances could not be opened.
table_instances_lost Performance_schema_table_instances_lost ASYNC COUNTER How many table instrument instances could not be created.
table_lock_stat_lost Performance_schema_table_lock_stat_lost ASYNC COUNTER The number of tables for which lock statistics were lost.
thread_classes_lost Performance_schema_thread_classes_lost ASYNC COUNTER How many thread instruments could not be loaded.
thread_instances_lost Performance_schema_thread_instances_lost ASYNC COUNTER The number of thread instances that could not be instrumented in the threads table.
users_lost Performance_schema_users_lost ASYNC COUNTER The number of times a row could not be added to the users table because it was full.

mysql.stats.handler Metrics

The mysql.stats.handler metrics correspond to the Handler_XXX status variables.

Table 35.6 mysql.perf_schema Metrics

Name Source Variable OTEL Type Description
commit Handler_commit ASYNC COUNTER The number of internal COMMIT statements.
delete Handler_delete ASYNC COUNTER The number of times that rows have been deleted from tables
discover Handler_discover ASYNC COUNTER The number of times that tables have been discovered.
external_lock Handler_external_lock ASYNC COUNTER The server increments this variable for each call to its external_lock() function, which generally occurs at the beginning and end of access to a table instance.
mrr_init Handler_mrr_init ASYNC COUNTER The number of times the server uses a storage engine's own Multi-Range Read implementation for table access.
prepare Handler_prepare ASYNC COUNTER A counter for the prepare phase of two-phase commit operations.
read_first Handler_read_first ASYNC COUNTER The number of times the first entry in an index was read.
read_key Handler_read_key ASYNC COUNTER The number of requests to read a row based on a key.
read_last Handler_read_last ASYNC COUNTER The number of requests to read the last key in an index.
read_next Handler_read_next ASYNC COUNTER The number of requests to read the next row in key order.
read_prev Handler_read_prev ASYNC COUNTER The number of requests to read the previous row in key order.
read_rnd Handler_read_rnd ASYNC COUNTER The number of requests to read a row based on a fixed position.
read_rnd_next Handler_read_rnd_next ASYNC COUNTER The number of requests to read the next row in the data file.
rollback Handler_rollback ASYNC COUNTER The number of requests for a storage engine to perform a rollback operation.
savepoint Handler_savepoint ASYNC COUNTER The number of requests for a storage engine to place a savepoint.
savepoint_rollback Handler_savepoint_rollback ASYNC COUNTER The number of requests for a storage engine to roll back to a savepoint.
update Handler_update ASYNC COUNTER The number of requests to update a row in a table.
write Handler_write ASYNC COUNTER The number of requests to insert a row in a table.

mysql.stats.myisam Metrics

Table 35.7 mysql.perf_schema Metrics

Name Source Variable OTEL Type Description
key_blocks_not_flushed Key_blocks_not_flushed ASYNC COUNTER The number of key blocks in the MyISAM key cache that have changed but have not yet been flushed to disk.
key_blocks_unused Key_blocks_unused ASYNC COUNTER The number of unused blocks in the MyISAM key cache.
key_blocks_used Key_blocks_used ASYNC COUNTER The number of used blocks in the MyISAM key cache.
key_read_requests Key_read_requests ASYNC COUNTER The number of requests to read a key block from the MyISAM key cache.
key_reads Key_reads ASYNC COUNTER The number of physical reads of a key block from disk into the MyISAM key cache.
key_write_requests Key_write_requests ASYNC COUNTER The number of requests to write a key block to the MyISAM key cache.
key_writes Key_writes ASYNC COUNTER The number of physical writes of a key block from the MyISAM key cache to disk.

mysql.stats.ssl Metrics

Table 35.8 mysql.stats.ssl Metrics

Name Source Variable OTEL Type Description
client_connects Ssl_client_connects ASYNC COUNTER The number of SSL connection attempts to an SSL-enabled replication source server.
connect_renegotiates Ssl_connect_renegotiates ASYNC COUNTER The number of negotiates needed to establish the connection to an SSL-enabled replication source server.
finished_accepts Ssl_finished_accepts ASYNC COUNTER The number of successful SSL connections to the server.
finished_connects Ssl_finished_connects ASYNC COUNTER The number of successful replica connections to an SSL-enabled replication source server.
session_cache_hits Ssl_session_cache_hits ASYNC COUNTER The number of SSL session cache hits.
session_cache_misses Ssl_session_cache_misses ASYNC COUNTER The number of SSL session cache misses.
session_cache_overflows Ssl_session_cache_overflows ASYNC COUNTER The number of SSL session cache overflows.
session_cache_size Ssl_session_cache_size ASYNC COUNTER The SSL session cache size.
session_cache_timeouts Ssl_session_cache_timeouts ASYNC COUNTER The number of SSL session cache timeouts.
used_session_cache_entries Ssl_used_session_cache_entries ASYNC COUNTER How many SSL session cache entries were used.
accept_renegotiates Ssl_accept_renegotiates ASYNC COUNTER The number of negotiates needed to establish the connection.
accepts Ssl_accepts ASYNC COUNTER The number of accepted SSL connections.
callback_cache_hits Ssl_callback_cache_hits ASYNC COUNTER The number of callback cache hits.

mysql.inno Metrics

Table 35.9 mysql.inno Metrics

Name Source Variable OTEL Type Description
dblwr_pages_written Innodb_dblwr_pages_written ASYNC COUNTER Number of pages that have been written for doublewrite operations
dblwr_writes Innodb_dblwr_writes ASYNC COUNTER Number of doublewrite operations that have been performed
redo_log_logical_size Innodb_redo_log_logical_size ASYNC GAUGE COUNTER LSN range size in bytes containing in-use redo log data.
redo_log_physical_size Innodb_redo_log_physical_size ASYNC GAUGE COUNTER Disk space in bytes currently consumed by all redo log files on disk, excluding spare redo log files
redo_log_capacity_resized Innodb_redo_log_capacity_resized ASYNC GAUGE COUNTER Redo log capacity in bytes for all redo log files, after the last completed capacity resize operation
log_waits Innodb_log_waits ASYNC COUNTER Number of log waits due to small log buffer
log_write_requests Innodb_log_write_requests ASYNC COUNTER Number of log write requests
log_writes Innodb_log_writes ASYNC COUNTER The number of physical writes to the InnoDB redo log file
os_log_fsyncs Innodb_os_log_fsyncs ASYNC COUNTER Number of fsync log writes.
os_log_pending_fsyncs Innodb_os_log_pending_fsyncs ASYNC GAUGE COUNTER Number of pending fsync writes.
os_log_pending_writes Innodb_os_log_pending_writes ASYNC GAUGE COUNTER Number of pending log file writes.
os_log_written Innodb_os_log_written ASYNC COUNTER Bytes of log written.
page_size Innodb_page_size ASYNC GAUGE COUNTER InnoDB page size in bytes.
pages_created Innodb_pages_created ASYNC COUNTER Number of pages created
pages_read Innodb_pages_read ASYNC COUNTER Number of pages read.
pages_written Innodb_pages_written ASYNC COUNTER Number of pages written.
row_lock_current_waits Innodb_row_lock_current_waits ASYNC GAUGE COUNTER Number of row locks currently being waited for.
row_lock_time Innodb_row_lock_time ASYNC COUNTER Time spent in acquiring row locks, in milliseconds
row_lock_time_avg Innodb_row_lock_time_avg ASYNC GAUGE COUNTER The average time to acquire a row lock, in milliseconds
row_lock_time_max Innodb_row_lock_time_max ASYNC GAUGE COUNTER The maximum time to acquire a row lock, in milliseconds.
row_lock_waits Innodb_row_lock_waits ASYNC COUNTER Number of times a row lock had to be waited for.
rows_deleted [`Innodb_rows_delete

（本文超出站点单文档体积上限，已截断）