stats: Add a function to report completion latency percentiles

[fio.git] / fio.c

diff --git a/fio.c b/fio.c
index 9e9106d55113b54785993649c38768824e6c755a..73964214d3468d93a4f0ed72f4ecbd330f57b9c6 100644 (file)
--- a/fio.c
+++ b/fio.c
@@ -550,13 +550,14 @@ sync_done:
 
                /*
                 * if we can queue more, do so. but check if there are
-                * completed io_u's first.
+                * completed io_u's first. Note that we can get BUSY even
+                * without IO queued, if the system is resource starved.
                 */
-               full = queue_full(td) || ret == FIO_Q_BUSY;
+               full = queue_full(td) || (ret == FIO_Q_BUSY && td->cur_depth);
                if (full || !td->o.iodepth_batch_complete) {
                        min_events = min(td->o.iodepth_batch_complete,
                                         td->cur_depth);
-                       if (full && !min_events)
+                       if (full && !min_events && td->o.iodepth_batch_complete != 0)
                                min_events = 1;
 
                        do {
@@ -710,13 +711,15 @@ sync_done:
                        break;
 
                /*
-                * See if we need to complete some commands
+                * See if we need to complete some commands. Note that we
+                * can get BUSY even without IO queued, if the system is
+                * resource starved.
                 */
-               full = queue_full(td) || ret == FIO_Q_BUSY;
+               full = queue_full(td) || (ret == FIO_Q_BUSY && td->cur_depth);
                if (full || !td->o.iodepth_batch_complete) {
                        min_evts = min(td->o.iodepth_batch_complete,
                                        td->cur_depth);
-                       if (full && !min_evts)
+                       if (full && !min_evts && td->o.iodepth_batch_complete != 0)
                                min_evts = 1;
 
                        if (__should_check_rate(td, 0) ||