hi i have run couple of fio runs. i am running this over raid1 device. i have captured blktrace for each run. I was going through the blktraces. what i have observed is there instances where there is commit happening to disk at say time stamp X. I was expecting a new IO to be submitted at X+1 time stamp. but i see next IO is submitted at time stamp Y. Y-X is more than 1. Is there any delay introduced from FIO between two fios. or what could be the probable reasons to see such delay? let me know if my understanding is wrong. Below is the excerpt from blktrace: 21378 8,32 3 9162 0.116015463 0 C WS 574576152 + 8 [0] 21379 8,16 3 10690 0.116020386 0 C WS 574576152 + 8 [0] 21380 9,0 0 1 0.120074779 8797 Q WS 131300520 + 8 [fitness] from lines 21379(C) to 21380(Q) there is lots of delay for submission of new IO. So i was thinking in lines of any delay from FIO between submissions of IO or they submit IO as soon as it is available. Question 2: I have also observed larger delays in Q-D values. which is more than D-C value. What could be the possible reasons for this behavior ? regards sampath -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
