use poll() and rbd_poll_io_events to speed up io retrieval.

diff --git a/configure b/configure
index e91ec2582406895772a19e80b20e36bedc32b372..833b6d33464b378382fbcdb8d7acca9f49fccb73 100755 (executable)
--- a/configure
+++ b/configure
@@ -1334,6 +1334,32 @@ if test "$disable_rbd" != "yes"  && compile_prog "" "-lrbd -lrados" "rbd"; then
 fi
 echo "Rados Block Device engine     $rbd"
 
+##########################################
+# check for rbd_poll
+rbd_poll="no"
+if test "$rbd" = "yes"; then
+cat > $TMPC << EOF
+#include <rbd/librbd.h>
+#include <sys/eventfd.h>
+
+int main(int argc, char **argv)
+{
+  rbd_image_t image;
+  rbd_completion_t comp;
+
+  int fd = eventfd(0, EFD_NONBLOCK);
+  rbd_set_image_notification(image, fd, EVENT_TYPE_EVENTFD);
+  rbd_poll_io_events(image, comp, 1);
+
+  return 0;
+}
+EOF
+if compile_prog "" "-lrbd -lrados" "rbd"; then
+  rbd_poll="yes"
+fi
+echo "rbd_poll                      $rbd_poll"
+fi
+
 ##########################################
 # check for rbd_invaidate_cache()
 rbd_inval="no"
@@ -1853,6 +1879,9 @@ fi
 if test "$rbd" = "yes" ; then
   output_sym "CONFIG_RBD"
 fi
+if test "$rbd_poll" = "yes" ; then
+  output_sym "CONFIG_RBD_POLL"
+fi
 if test "$rbd_inval" = "yes" ; then
   output_sym "CONFIG_RBD_INVAL"
 fi

diff --git a/engines/rbd.c b/engines/rbd.c
index 5e17fbe73a7fab5cc1b04431c3df7965d76acd01..02fe655202ca6320617493e994df80693b6a3cf9 100644 (file)
--- a/engines/rbd.c
+++ b/engines/rbd.c
@@ -13,6 +13,12 @@
 #include <zipkin_c.h>
 #endif
 
+#ifdef CONFIG_RBD_POLL
+/* add for poll */
+#include <poll.h>
+#include <sys/eventfd.h>
+#endif
+
 struct fio_rbd_iou {
        struct io_u *io_u;
        rbd_completion_t completion;
@@ -29,6 +35,9 @@ struct rbd_data {
        rbd_image_t image;
        struct io_u **aio_events;
        struct io_u **sort_events;
+#ifdef CONFIG_RBD_POLL
+       int fd; /* add for poll */
+#endif
 };
 
 struct rbd_options {
@@ -104,6 +113,11 @@ static int _fio_setup_rbd_data(struct thread_data *td,
        if (!rbd)
                goto failed;
 
+#ifdef CONFIG_RBD_POLL
+       /* add for poll, init fd: -1 */
+       rbd->fd = -1;
+#endif
+
        rbd->aio_events = calloc(td->o.iodepth, sizeof(struct io_u *));
        if (!rbd->aio_events)
                goto failed;
@@ -188,8 +202,30 @@ static int _fio_rbd_connect(struct thread_data *td)
                log_err("rbd_open failed.\n");
                goto failed_open;
        }
+
+#ifdef CONFIG_RBD_POLL
+       /* add for rbd poll */
+       rbd->fd = eventfd(0, EFD_NONBLOCK);
+       if (rbd->fd < 0) {
+               log_err("eventfd failed.\n");
+               goto failed_open;
+       }
+    
+       r = rbd_set_image_notification(rbd->image, rbd->fd, EVENT_TYPE_EVENTFD);
+       if (r < 0) {
+               log_err("rbd_set_image_notification failed.\n");
+               goto failed_notify;
+       }
+#endif
+
        return 0;
 
+#ifdef CONFIG_RBD_POLL
+failed_notify:
+       close(rbd->fd);
+       rbd->fd = -1;
+#endif
+
 failed_open:
        rados_ioctx_destroy(rbd->io_ctx);
        rbd->io_ctx = NULL;
@@ -205,6 +241,14 @@ static void _fio_rbd_disconnect(struct rbd_data *rbd)
        if (!rbd)
                return;
 
+#ifdef CONFIG_RBD_POLL
+       /* close eventfd */
+       if (rbd->fd >= 0) {
+               close(rbd->fd);
+               rbd->fd = -1;
+       }
+#endif
+
        /* shutdown everything */
        if (rbd->image) {
                rbd_close(rbd->image);
@@ -304,10 +348,33 @@ static int rbd_iter_events(struct thread_data *td, unsigned int *events,
        struct rbd_data *rbd = td->io_ops_data;
        unsigned int this_events = 0;
        struct io_u *io_u;
-       int i, sidx;
+       int i, sidx = 0;
+
+#ifdef CONFIG_RBD_POLL
+       int ret = 0;
+       int event_num = 0;
+       struct fio_rbd_iou *fri = NULL;
+       rbd_completion_t comps[min_evts];
+
+       struct pollfd pfd;
+       pfd.fd = rbd->fd;
+       pfd.events = POLLIN;
 
-       sidx = 0;
+       ret = poll(&pfd, 1, -1);
+       if (ret <= 0) {
+               return 0;
+       }
+        
+       assert(pfd.revents & POLLIN);
+
+       event_num = rbd_poll_io_events(rbd->image, comps, min_evts);
+
+       for (i = 0; i < event_num; i++) {
+               fri = rbd_aio_get_arg(comps[i]);
+               io_u = fri->io_u;
+#else
        io_u_qiter(&td->io_u_all, io_u, i) {
+#endif
                if (!(io_u->flags & IO_U_F_FLIGHT))
                        continue;
                if (rbd_io_u_seen(io_u))