io_size vs. time_based discrepancy

[fio.git] / backend.c

diff --git a/backend.c b/backend.c
index b180196e4c4ec5b16d61120efaf14c9a2abdbf1f..224736f4c963dcef68db671b39b83ec9ed763758 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -35,6 +35,7 @@
 #include <sys/wait.h>
 #include <sys/ipc.h>
 #include <sys/mman.h>
+#include <math.h>
 
 #include "fio.h"
 #ifndef FIO_NO_HAVE_SHM_H
@@ -447,7 +448,7 @@ static int wait_for_completions(struct thread_data *td, struct timeval *time)
         * if the queue is full, we MUST reap at least 1 event
         */
        min_evts = min(td->o.iodepth_batch_complete_min, td->cur_depth);
-    if ((full && !min_evts) || !td->o.iodepth_batch_complete_min)
+       if ((full && !min_evts) || !td->o.iodepth_batch_complete_min)
                min_evts = 1;
 
        if (time && (__should_check_rate(td, DDIR_READ) ||
@@ -775,17 +776,30 @@ static int io_complete_bytes_exceeded(struct thread_data *td)
  */
 static long long usec_for_io(struct thread_data *td, enum fio_ddir ddir)
 {
-       uint64_t secs, remainder, bps, bytes;
+       uint64_t secs, remainder, bps, bytes, iops;
 
        assert(!(td->flags & TD_F_CHILD));
        bytes = td->rate_io_issue_bytes[ddir];
        bps = td->rate_bps[ddir];
-       if (bps) {
+
+       if (td->o.rate_process == RATE_PROCESS_POISSON) {
+               uint64_t val;
+               iops = bps / td->o.bs[ddir];
+               val = (int64_t) (1000000 / iops) *
+                               -logf(__rand_0_1(&td->poisson_state));
+               if (val) {
+                       dprint(FD_RATE, "poisson rate iops=%llu\n",
+                                       (unsigned long long) 1000000 / val);
+               }
+               td->last_usec += val;
+               return td->last_usec;
+       } else if (bps) {
                secs = bytes / bps;
                remainder = bytes % bps;
                return remainder * 1000000 / bps + secs * 1000000;
-       } else
-               return 0;
+       }
+
+       return 0;
 }
 
 /*
@@ -854,7 +868,7 @@ static uint64_t do_io(struct thread_data *td)
                if (flow_threshold_exceeded(td))
                        continue;
 
-               if (bytes_issued >= total_bytes)
+               if (!td->o.time_based && bytes_issued >= total_bytes)
                        break;
 
                io_u = get_io_u(td);
@@ -1559,27 +1573,28 @@ static void *thread_main(void *data)
 
        fio_gettime(&td->epoch, NULL);
        fio_getrusage(&td->ru_start);
+       memcpy(&td->bw_sample_time, &td->epoch, sizeof(td->epoch));
+       memcpy(&td->iops_sample_time, &td->epoch, sizeof(td->epoch));
+
+       if (o->ratemin[DDIR_READ] || o->ratemin[DDIR_WRITE] ||
+                       o->ratemin[DDIR_TRIM]) {
+               memcpy(&td->lastrate[DDIR_READ], &td->bw_sample_time,
+                                       sizeof(td->bw_sample_time));
+               memcpy(&td->lastrate[DDIR_WRITE], &td->bw_sample_time,
+                                       sizeof(td->bw_sample_time));
+               memcpy(&td->lastrate[DDIR_TRIM], &td->bw_sample_time,
+                                       sizeof(td->bw_sample_time));
+       }
+
        clear_state = 0;
        while (keep_running(td)) {
                uint64_t verify_bytes;
 
                fio_gettime(&td->start, NULL);
-               memcpy(&td->bw_sample_time, &td->start, sizeof(td->start));
-               memcpy(&td->iops_sample_time, &td->start, sizeof(td->start));
                memcpy(&td->tv_cache, &td->start, sizeof(td->start));
 
-               if (o->ratemin[DDIR_READ] || o->ratemin[DDIR_WRITE] ||
-                               o->ratemin[DDIR_TRIM]) {
-                       memcpy(&td->lastrate[DDIR_READ], &td->bw_sample_time,
-                                               sizeof(td->bw_sample_time));
-                       memcpy(&td->lastrate[DDIR_WRITE], &td->bw_sample_time,
-                                               sizeof(td->bw_sample_time));
-                       memcpy(&td->lastrate[DDIR_TRIM], &td->bw_sample_time,
-                                               sizeof(td->bw_sample_time));
-               }
-
                if (clear_state)
-                       clear_io_state(td);
+                       clear_io_state(td, 0);
 
                prune_io_piece_log(td);
 
@@ -1617,7 +1632,7 @@ static void *thread_main(void *data)
                    (td->io_ops->flags & FIO_UNIDIR))
                        continue;
 
-               clear_io_state(td);
+               clear_io_state(td, 0);
 
                fio_gettime(&td->start, NULL);