Implement new Rate Control

[fio.git] / backend.c

diff --git a/backend.c b/backend.c
index 3eafff6e6bbbcca9bc8ef3594ff3f74e0e222013..d5b260a81c896fbcbe8c2ddf581d584225f69067 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -762,6 +762,25 @@ static int io_complete_bytes_exceeded(struct thread_data *td)
        return bytes >= limit || exceeds_number_ios(td);
 }
 
+/*
+ * used to calculate the next io time for rate control
+ *
+ */
+static long long usec_for_io(struct thread_data *td, enum fio_ddir ddir)
+{
+       uint64_t secs, remainder, bps, bytes;
+
+       assert(!(td->flags & TD_F_CHILD));
+       bytes = td->rate_io_issue_bytes[ddir];
+       bps = td->rate_bps[ddir];
+       if (bps) {
+               secs = bytes / bps;
+               remainder = bytes % bps;
+               return remainder * 1000000 / bps + secs * 1000000;
+       } else
+               return 0;
+}
+
 /*
  * Main IO worker function. It retrieves io_u's to process and queues
  * and reaps them, checking for rate and errors along the way.
@@ -891,9 +910,16 @@ static uint64_t do_io(struct thread_data *td)
                        if (td->error)
                                break;
                        ret = workqueue_enqueue(&td->io_wq, io_u);
+
+                       if (should_check_rate(td))
+                               td->rate_next_io_time[ddir] = usec_for_io(td, ddir);
+
                } else {
                        ret = td_io_queue(td, io_u);
 
+                       if (should_check_rate(td))
+                               td->rate_next_io_time[ddir] = usec_for_io(td, ddir);
+
                        if (io_queue_event(td, io_u, &ret, ddir, &bytes_issued, 0, &comp_time))
                                break;
 
@@ -924,7 +950,7 @@ reap:
                }
                if (!in_ramp_time(td) && td->o.latency_target)
                        lat_target_check(td);
-
+                                       
                if (td->o.thinktime) {
                        unsigned long long b;