Add option for refilling IO buffers on each submit

[fio.git] / io_u.c

diff --git a/io_u.c b/io_u.c
index 7f52a243fbdbc8e2b12706c1f45c52716729a8ab..06fb3cef80c7fb71c1c6aad29e1936b27e1b9b19 100644 (file)
--- a/io_u.c
+++ b/io_u.c
@@ -6,6 +6,7 @@
 #include <assert.h>
 
 #include "fio.h"
+#include "hash.h"
 
 /*
  * Change this define to play with the timeout handling
@@ -188,7 +189,14 @@ static int get_next_offset(struct thread_data *td, struct io_u *io_u)
                        b = (f->last_pos - f->file_offset) / td->o.min_bs[ddir];
        }
 
-       io_u->offset = (b * td->o.min_bs[ddir]) + f->file_offset;
+       io_u->offset = b * td->o.min_bs[ddir];
+       if (io_u->offset >= f->io_size) {
+               dprint(FD_IO, "get_next_offset: offset %llu >= io_size %llu\n",
+                                       io_u->offset, f->io_size);
+               return 1;
+       }
+
+       io_u->offset += f->file_offset;
        if (io_u->offset >= f->real_file_size) {
                dprint(FD_IO, "get_next_offset: offset %llu >= size %llu\n",
                                        io_u->offset, f->real_file_size);
@@ -312,17 +320,21 @@ static enum fio_ddir get_rw_ddir(struct thread_data *td)
                return DDIR_WRITE;
 }
 
+static void put_file_log(struct thread_data *td, struct fio_file *f)
+{
+       int ret = put_file(td, f);
+
+       if (ret)
+               td_verror(td, ret, "file close");
+}
+
 void put_io_u(struct thread_data *td, struct io_u *io_u)
 {
        assert((io_u->flags & IO_U_F_FREE) == 0);
        io_u->flags |= IO_U_F_FREE;
 
-       if (io_u->file) {
-               int ret = put_file(td, io_u->file);
-
-               if (ret)
-                       td_verror(td, ret, "file close");
-       }
+       if (io_u->file)
+               put_file_log(td, io_u->file);
 
        io_u->file = NULL;
        list_del(&io_u->list);
@@ -650,6 +662,16 @@ set_file:
                if (!fill_io_u(td, io_u))
                        break;
 
+               /*
+                * optimization to prevent close/open of the same file. This
+                * way we preserve queueing etc.
+                */
+               if (td->o.nr_files == 1 && td->o.time_based) {
+                       put_file_log(td, f);
+                       fio_file_reset(f);
+                       goto set_file;
+               }
+
                /*
                 * td_io_close() does a put_file() as well, so no need to
                 * do that here.
@@ -759,6 +781,9 @@ struct io_u *get_io_u(struct thread_data *td)
        io_u->endpos = io_u->offset + io_u->buflen;
        io_u->xfer_buf = io_u->buf;
        io_u->xfer_buflen = io_u->buflen;
+
+       if (td->o.refill_buffers && io_u->ddir == DDIR_WRITE)
+               io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
 out:
        if (!td_io_prep(td, io_u)) {
                fio_gettime(&io_u->start_time, NULL);
@@ -922,6 +947,23 @@ void io_u_queued(struct thread_data *td, struct io_u *io_u)
        add_slat_sample(td, io_u->ddir, slat_time);
 }
 
+/*
+ * "randomly" fill the buffer contents
+ */
+void io_u_fill_buffer(struct thread_data *td, struct io_u *io_u,
+                     unsigned int max_bs)
+{
+       long *ptr = io_u->buf;
+
+       if (!td->o.zero_buffers) {
+               while ((void *) ptr - io_u->buf < max_bs) {
+                       *ptr = rand() * GOLDEN_RATIO_PRIME;
+                       ptr++;
+               }
+       } else
+               memset(ptr, 0, max_bs);
+}
+
 #ifdef FIO_USE_TIMEOUT
 void io_u_set_timeout(struct thread_data *td)
 {