- deviation). This is the time it took to submit the I/O. For
- sync I/O this row is not displayed as the slat is really the
- completion latency (since queue/complete is one operation there).
- This value can be in nanoseconds, microseconds or milliseconds ---
- fio will choose the most appropriate base and print that (in the
- example above nanoseconds was the best scale). Note: in :option:`--minimal` mode
- latencies are always expressed in microseconds.
+ deviation). This is the time from when fio initialized the I/O
+ to submission. For synchronous ioengines this includes the time
+ up until just before the ioengine's queue function is called.
+ For asynchronous ioengines this includes the time up through the
+ completion of the ioengine's queue function (and commit function
+ if it is defined). For sync I/O this row is not displayed as the
+ slat is negligible. This value can be in nanoseconds,
+ microseconds or milliseconds --- fio will choose the most
+ appropriate base and print that (in the example above
+ nanoseconds was the best scale). Note: in :option:`--minimal`
+ mode latencies are always expressed in microseconds.