Measuring semop() +1 operations without undo
average over 10000 operations
number of operations per second: 129181
clock secs:7.7411e-06(=7.7411 usecs)  cpu secs:8e-06(=8 usecs)

Measuring semop() -1 operations without undo
average over 10000 operations
number of operations per second: 130161
clock secs:7.6828e-06(=7.6828 usecs)  cpu secs:7e-06(=7 usecs)

Measuring semop() +1 operations with undo
average over 10000 operations
number of operations per second: 127068
clock secs:7.8698e-06(=7.8698 usecs)  cpu secs:8e-06(=8 usecs)

Measuring semop() -1 operations with undo
average over 10000 operations
number of operations per second: 127107
clock secs:7.8674e-06(=7.8674 usecs)  cpu secs:8e-06(=8 usecs)