[PATCH] fio: expand latency numbers for sync io.

diff --git a/README.fio b/README.fio
index 66022aa3d874e07a839bc9c0544dcd1ac1313f23..f3aad7d0e045cd8399cea64a7bf44fccfa7bdb65 100644 (file)
--- a/README.fio
+++ b/README.fio
@@ -118,6 +118,8 @@ Threads now running: 2 : [ww] [5.73% done]
 The characters inside the square brackets denote the current status of
 each thread. The possible values (in typical life cycle order) are:
 
+Idle   Run
+----    ---
 P              Thread setup, but not started.
 C              Thread created and running, but not doing anything yet
        R       Running, doing sequential reads.
@@ -151,9 +153,13 @@ bw=                Average bandwidth rate
 runt=          The runtime of that thread
        slat=   Submission latency (avg being the average, dev being the
                standard deviation). This is the time it took to submit
-               the io.
+               the io. For sync io, the slat is really the completion
+               latency, since queue/complete is one operation there.
        clat=   Completion latency. Same names as slat, this denotes the
-               time from submission to completion of the io pieces.
+               time from submission to completion of the io pieces. For
+               sync io, clat will usually be equal (or very close) to 0,
+               as the time from submit to complete is basically just
+               CPU time (io has already been done, see slat explanation).
        bw=     Bandwidth. Same names as the xlat stats, but also includes
                an approximate percentage of total aggregate bandwidth
                this thread received in this group. This last value is