Add support for 'bssplit' option, fine grained block size contrl
[fio.git] / io_u.c
diff --git a/io_u.c b/io_u.c
index 93c451c..7890a87 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -186,7 +186,21 @@ static unsigned int get_next_buflen(struct thread_data *td, struct io_u *io_u)
                buflen = td->o.min_bs[ddir];
        else {
                r = os_random_long(&td->bsrange_state);
-               buflen = (unsigned int) (1 + (double) (td->o.max_bs[ddir] - 1) * r / (RAND_MAX + 1.0));
+               if (!td->o.bssplit_nr)
+                       buflen = (unsigned int) (1 + (double) (td->o.max_bs[ddir] - 1) * r / (RAND_MAX + 1.0));
+               else {
+                       long perc = 0;
+                       unsigned int i;
+
+                       for (i = 0; i < td->o.bssplit_nr; i++) {
+                               struct bssplit *bsp = &td->o.bssplit[i];
+
+                               buflen = bsp->bs;
+                               perc += bsp->perc;
+                               if (r <= ((LONG_MAX / 100L) * perc))
+                                       break;
+                       }
+               }
                if (!td->o.bs_unaligned)
                        buflen = (buflen + td->o.min_bs[ddir] - 1) & ~(td->o.min_bs[ddir] - 1);
        }