Only log the period mean if we have samples
We can't use the mean value to determine that, it could in theory
be 0.0 and still have valid samples.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/stat.c b/stat.c
index 7de2362..c921f5f 100644
--- a/stat.c
+++ b/stat.c
@@ -1145,11 +1145,17 @@
iolog->nr_samples++;
}
+static inline void reset_io_stat(struct io_stat *ios)
+{
+ ios->max_val = ios->min_val = ios->samples = 0;
+ ios->mean.u.f = ios->S.u.f = 0;
+}
+
static void add_log_sample(struct thread_data *td, struct io_log *iolog,
unsigned long val, enum fio_ddir ddir,
unsigned int bs)
{
- unsigned long elapsed, this_window, mr, mw;
+ unsigned long elapsed, this_window;
if (!ddir_rw(ddir))
return;
@@ -1170,20 +1176,34 @@
*/
add_stat_sample(&iolog->avg_window[ddir], val);
+ /*
+ * If period hasn't passed, adding the above sample is all we
+ * need to do.
+ */
this_window = elapsed - iolog->avg_last;
if (this_window < iolog->avg_msec)
return;
- mr = iolog->avg_window[DDIR_READ].mean.u.f;
- mw = iolog->avg_window[DDIR_WRITE].mean.u.f;
+ /*
+ * Note an entry in the log. Use the mean from the logged samples,
+ * making sure to properly round up. Only write a log entry if we
+ * had actual samples done.
+ */
+ if (iolog->avg_window[DDIR_READ].samples) {
+ unsigned long mr;
- if (mr)
+ mr = iolog->avg_window[DDIR_READ].mean.u.f + 0.50;
__add_log_sample(iolog, mr, DDIR_READ, 0, elapsed);
- if (mw)
- __add_log_sample(iolog, mw, DDIR_WRITE, 0, elapsed);
+ }
+ if (iolog->avg_window[DDIR_WRITE].samples) {
+ unsigned long mw;
- memset(&iolog->avg_window[DDIR_READ], 0, sizeof(struct io_stat));
- memset(&iolog->avg_window[DDIR_WRITE], 0, sizeof(struct io_stat));
+ mw = iolog->avg_window[DDIR_WRITE].mean.u.f + 0.50;
+ __add_log_sample(iolog, mw, DDIR_WRITE, 0, elapsed);
+ }
+
+ reset_io_stat(&iolog->avg_window[DDIR_READ]);
+ reset_io_stat(&iolog->avg_window[DDIR_WRITE]);
iolog->avg_last = elapsed;
}