Tested on both PS 5.1 and PS 5.5 RPM builds on CentOS 6.3 64 bit. clock_gettime is used and CPU statistics are collected.
PS 5.5 :
mysql> select * from information_schema.user_statistics\G *************************** 1. row *************************** USER: root TOTAL_CONNECTIONS: 36 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 1417 BUSY_TIME: 843 CPU_TIME: 89 BYTES_RECEIVED: 36892209 BYTES_SENT: 0 BINLOG_BYTES_WRITTEN: 26470995 ROWS_FETCHED: 8000828 ROWS_UPDATED: 132874 TABLE_ROWS_READ: 10727957 SELECT_COMMANDS: 360206 UPDATE_COMMANDS: 102888 OTHER_COMMANDS: 51446 COMMIT_TRANSACTIONS: 25727 ROLLBACK_TRANSACTIONS: 0 DENIED_CONNECTIONS: 0 LOST_CONNECTIONS: 19 ACCESS_DENIED: 0 EMPTY_QUERIES: 0 TOTAL_SSL_CONNECTIONS: 0 1 row in set (0.00 sec)
PS 5.1:
mysql> select * from information_schema.user_statistics\G *************************** 1. row *************************** USER: root TOTAL_CONNECTIONS: 29 CONCURRENT_CONNECTIONS: 0 CONNECTED_TIME: 566 BUSY_TIME: 389 CPU_TIME: 48 BYTES_RECEIVED: 10275334 BYTES_SENT: 21120 BINLOG_BYTES_WRITTEN: 12192166 ROWS_FETCHED: 4035649 ROWS_UPDATED: 110475 TABLE_ROWS_READ: 6748195 SELECT_COMMANDS: 3 UPDATE_COMMANDS: 5 OTHER_COMMANDS: 16113 COMMIT_TRANSACTIONS: 16096 ROLLBACK_TRANSACTIONS: 2 DENIED_CONNECTIONS: 0 LOST_CONNECTIONS: 24 ACCESS_DENIED: 0 EMPTY_QUERIES: 0 1 row in set (0.00 sec)
Also, tested with strace and gdb:
strace -f -e trace=clock_gettime -p 1698 Process 1698 attached with 19 threads - interrupt to quit Process 8762 detached Process 8827 attached [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 331874}) = 0 [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 792574}) = 0 [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 956722}) = 0 [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 1228094}) = 0 [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 17605198}) = 0 [pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 17878064}) = 0
GDB output: http://sprunge.us/ZBdj
Tested on both PS 5.1 and PS 5.5 RPM builds on CentOS 6.3 64 bit. clock_gettime is used and CPU statistics are collected.
PS 5.5 :
mysql> select * from information_ schema. user_statistics \G ******* ******* ****** 1. row ******* ******* ******* ******
USER: root CONNECTIONS: 36 CONNECTIONS: 0
CONNECTED_ TIME: 1417
BUSY_ TIME: 843
CPU_TIME: 89
BYTES_ RECEIVED: 36892209
BYTES_ SENT: 0 BYTES_WRITTEN: 26470995
ROWS_ FETCHED: 8000828
ROWS_ UPDATED: 132874
TABLE_ROWS_ READ: 10727957
SELECT_ COMMANDS: 360206
UPDATE_ COMMANDS: 102888
OTHER_ COMMANDS: 51446 TRANSACTIONS: 25727 TRANSACTIONS: 0 CONNECTIONS: 0 CONNECTIONS: 19
ACCESS_ DENIED: 0
EMPTY_ QUERIES: 0 SSL_CONNECTIONS : 0
*******
TOTAL_
CONCURRENT_
BINLOG_
COMMIT_
ROLLBACK_
DENIED_
LOST_
TOTAL_
1 row in set (0.00 sec)
PS 5.1:
mysql> select * from information_ schema. user_statistics \G ******* ******* ****** 1. row ******* ******* ******* ******
USER: root CONNECTIONS: 29 CONNECTIONS: 0
CONNECTED_ TIME: 566
BUSY_ TIME: 389
CPU_TIME: 48
BYTES_ RECEIVED: 10275334
BYTES_ SENT: 21120 BYTES_WRITTEN: 12192166
ROWS_ FETCHED: 4035649
ROWS_ UPDATED: 110475
TABLE_ROWS_ READ: 6748195
SELECT_ COMMANDS: 3
UPDATE_ COMMANDS: 5
OTHER_ COMMANDS: 16113 TRANSACTIONS: 16096 TRANSACTIONS: 2 CONNECTIONS: 0 CONNECTIONS: 24
ACCESS_ DENIED: 0
EMPTY_ QUERIES: 0
*******
TOTAL_
CONCURRENT_
BINLOG_
COMMIT_
ROLLBACK_
DENIED_
LOST_
1 row in set (0.00 sec)
Also, tested with strace and gdb:
strace -f -e trace=clock_gettime -p 1698
Process 1698 attached with 19 threads - interrupt to quit
Process 8762 detached
Process 8827 attached
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 331874}) = 0
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 792574}) = 0
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 956722}) = 0
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 1228094}) = 0
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 17605198}) = 0
[pid 8827] clock_gettime(0x3 /* CLOCK_??? */, {0, 17878064}) = 0
GDB output: http:// sprunge. us/ZBdj