The Performance Schema file_summary_by_instance
table contains file events summarized by instance. It contains the following columns:
FILE_NAME
File name.
EVENT_NAME
Event name.
OBJECT_INSTANCE_BEGIN
Address in memory. Together with FILE_NAME and EVENT_NAME uniquely identifies a row.
COUNT_STAR
Number of summarized events
SUM_TIMER_WAIT
Total wait time of the summarized events that are timed.
MIN_TIMER_WAIT
Minimum wait time of the summarized events that are timed.
AVG_TIMER_WAIT
Average wait time of the summarized events that are timed.
MAX_TIMER_WAIT
Maximum wait time of the summarized events that are timed.
COUNT_READ
Number of all read operations, including FGETS, FGETC, FREAD, and READ.
SUM_TIMER_READ
Total wait time of all read operations that are timed.
MIN_TIMER_READ
Minimum wait time of all read operations that are timed.
AVG_TIMER_READ
Average wait time of all read operations that are timed.
MAX_TIMER_READ
Maximum wait time of all read operations that are timed.
SUM_NUMBER_OF_BYTES_READ
Bytes read by read operations.
COUNT_WRITE
Number of all write operations, including FPUTS, FPUTC, FPRINTF, VFPRINTF, FWRITE, and PWRITE.
SUM_TIMER_WRITE
Total wait time of all write operations that are timed.
MIN_TIMER_WRITE
Minimum wait time of all write operations that are timed.
AVG_TIMER_WRITE
Average wait time of all write operations that are timed.
MAX_TIMER_WRITE
Maximum wait time of all write operations that are timed.
SUM_NUMBER_OF_BYTES_WRITE
Bytes written by write operations.
COUNT_MISC
Number of all miscellaneous operations not counted above, including CREATE, DELETE, OPEN, CLOSE, STREAM_OPEN, STREAM_CLOSE, SEEK, TELL, FLUSH, STAT, FSTAT, CHSIZE, RENAME, and SYNC.
SUM_TIMER_MISC
Total wait time of all miscellaneous operations that are timed.
MIN_TIMER_MISC
Minimum wait time of all miscellaneous operations that are timed.
AVG_TIMER_MISC
Average wait time of all miscellaneous operations that are timed.
MAX_TIMER_MISC
Maximum wait time of all miscellaneous operations that are timed.
I/O operations can be avoided by caching, in which case they will not be recorded in this table.
You can TRUNCATE the table, which will reset all counters to zero.
SELECT * FROM file_summary_by_instance\G
...
*************************** 204. row ***************************
FILE_NAME: /var/lib/mysql/test/db.opt
EVENT_NAME: wait/io/file/sql/dbopt
OBJECT_INSTANCE_BEGIN: 140578961971264
COUNT_STAR: 6
SUM_TIMER_WAIT: 39902495024
MIN_TIMER_WAIT: 177888
AVG_TIMER_WAIT: 6650415692
MAX_TIMER_WAIT: 21026400404
COUNT_READ: 1
SUM_TIMER_READ: 21026400404
MIN_TIMER_READ: 21026400404
AVG_TIMER_READ: 21026400404
MAX_TIMER_READ: 21026400404
SUM_NUMBER_OF_BYTES_READ: 65
COUNT_WRITE: 0
SUM_TIMER_WRITE: 0
MIN_TIMER_WRITE: 0
AVG_TIMER_WRITE: 0
MAX_TIMER_WRITE: 0
SUM_NUMBER_OF_BYTES_WRITE: 0
COUNT_MISC: 5
SUM_TIMER_MISC: 18876094620
MIN_TIMER_MISC: 177888
AVG_TIMER_MISC: 3775218924
MAX_TIMER_MISC: 18864558060
*************************** 205. row ***************************
FILE_NAME: /var/log/mysql/mariadb-bin.000157
EVENT_NAME: wait/io/file/sql/binlog
OBJECT_INSTANCE_BEGIN: 140578961971968
COUNT_STAR: 6
SUM_TIMER_WAIT: 73985877680
MIN_TIMER_WAIT: 251136
AVG_TIMER_WAIT: 12330979468
MAX_TIMER_WAIT: 73846656340
COUNT_READ: 0
SUM_TIMER_READ: 0
MIN_TIMER_READ: 0
AVG_TIMER_READ: 0
MAX_TIMER_READ: 0
SUM_NUMBER_OF_BYTES_READ: 0
COUNT_WRITE: 2
SUM_TIMER_WRITE: 62583004
MIN_TIMER_WRITE: 27630192
AVG_TIMER_WRITE: 31291284
MAX_TIMER_WRITE: 34952812
SUM_NUMBER_OF_BYTES_WRITE: 369
COUNT_MISC: 4
SUM_TIMER_MISC: 73923294676
MIN_TIMER_MISC: 251136
AVG_TIMER_MISC: 18480823560
MAX_TIMER_MISC: 73846656340
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