As of MySQL 5.6.3, the users
table contains a row for each user who has connected to the
MySQL server. For each user name, the table counts the current
and total number of connections. The table size is autosized
at server startup. To set the table size explicitly, set the
performance_schema_users_size
system variable at server startup. To disable user statistics,
set this variable to 0.
The users table has the following
columns. For a description of how the Performance Schema
maintains rows in this table, including the effect of
TRUNCATE TABLE, see
Section 22.10.7, “Performance Schema Connection Tables”.
USER
The client user name for the connection. This is
NULL for an internal thread, or for a
user session that failed to authenticate.
CURRENT_CONNECTIONS
The current number of connections for the user.
TOTAL_CONNECTIONS
The total number of connections for the user.