Fix Runtime, IOPS, bandwidth recorded incorrectly
authorBrian Fulton <bfulton@google.com>
Mon, 4 May 2015 22:07:10 +0000 (16:07 -0600)
committerJens Axboe <axboe@fb.com>
Mon, 4 May 2015 22:07:10 +0000 (16:07 -0600)
This happens with small sized timed_based runs. Change runtime
tabulation back to microseconds to handle sub millisecond loops.

Signed-off-by: Jens Axboe <axboe@fb.com>
backend.c

index 65a3e18..e87c5f8 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -363,6 +363,20 @@ static inline int runtime_exceeded(struct thread_data *td, struct timeval *t)
        return 0;
 }
 
+/*
+ * We need to update the runtime consistently in ms, but keep a running
+ * tally of the current elapsed time in microseconds for sub millisecond
+ * updates.
+ */
+static inline void update_runtime(struct thread_data *td,
+                                 unsigned long long *elapsed_us,
+                                 const enum fio_ddir ddir)
+{
+       td->ts.runtime[ddir] -= (elapsed_us[ddir] + 999) / 1000;
+       elapsed_us[ddir] += utime_since_now(&td->start);
+       td->ts.runtime[ddir] += (elapsed_us[ddir] + 999) / 1000;
+}
+
 static int break_on_this_error(struct thread_data *td, enum fio_ddir ddir,
                               int *retptr)
 {
@@ -1306,7 +1320,7 @@ static void io_workqueue_fn(struct thread_data *td, struct io_u *io_u)
  */
 static void *thread_main(void *data)
 {
-       unsigned long long elapsed;
+       unsigned long long elapsed_us[DDIR_RWDIR_CNT] = { 0, };
        struct thread_data *td = data;
        struct thread_options *o = &td->o;
        pthread_condattr_t attr;
@@ -1544,18 +1558,12 @@ static void *thread_main(void *data)
                check_update_rusage(td);
 
                fio_mutex_down(stat_mutex);
-               if (td_read(td) && td->io_bytes[DDIR_READ]) {
-                       elapsed = mtime_since_now(&td->start);
-                       td->ts.runtime[DDIR_READ] += elapsed;
-               }
-               if (td_write(td) && td->io_bytes[DDIR_WRITE]) {
-                       elapsed = mtime_since_now(&td->start);
-                       td->ts.runtime[DDIR_WRITE] += elapsed;
-               }
-               if (td_trim(td) && td->io_bytes[DDIR_TRIM]) {
-                       elapsed = mtime_since_now(&td->start);
-                       td->ts.runtime[DDIR_TRIM] += elapsed;
-               }
+               if (td_read(td) && td->io_bytes[DDIR_READ])
+                       update_runtime(td, elapsed_us, DDIR_READ);
+               if (td_write(td) && td->io_bytes[DDIR_WRITE])
+                       update_runtime(td, elapsed_us, DDIR_WRITE);
+               if (td_trim(td) && td->io_bytes[DDIR_TRIM])
+                       update_runtime(td, elapsed_us, DDIR_TRIM);
                fio_gettime(&td->start, NULL);
                fio_mutex_up(stat_mutex);
 
@@ -1579,7 +1587,7 @@ static void *thread_main(void *data)
                check_update_rusage(td);
 
                fio_mutex_down(stat_mutex);
-               td->ts.runtime[DDIR_READ] += mtime_since_now(&td->start);
+               update_runtime(td, elapsed_us, DDIR_READ);
                fio_gettime(&td->start, NULL);
                fio_mutex_up(stat_mutex);