diff --git a/xenvm/lvcreate.ml b/xenvm/lvcreate.ml
index 11f6cb2..856ac0b 100644
--- a/xenvm/lvcreate.ml
+++ b/xenvm/lvcreate.ml
@@ -5,7 +5,7 @@ open Lwt
 
 
 (* lvcreate -n <name> vgname -l <size_in_percent> -L <size_in_mb> --addtag tag *)
-let lvcreate copts lv_name real_size percent_size tags vg_name =
+let lvcreate copts lv_name real_size percent_size tags vg_name action =
   let open Xenvm_common in
   let info = Lwt_main.run (
     get_vg_info_t copts vg_name >>= fun info ->
@@ -35,7 +35,10 @@ let lvcreate copts lv_name real_size percent_size tags vg_name =
         | e -> fail e
     ) >>= fun () ->
     return info) in
-  match info with | Some i -> Lvchange.lvchange_activate copts vg_name lv_name (Some i.local_device) false | None -> ()
+  match action with
+  | Some Xenvm_common.Activate ->
+    (match info with | Some i -> Lvchange.lvchange_activate copts vg_name lv_name (Some i.local_device) false | None -> ())
+  | _ -> ()
 
 let lv_name_arg =
   let doc = "Gives the name of the LV to be created. This must be unique within the volume group. " in
@@ -55,7 +58,7 @@ let lvcreate_cmd =
     `S "DESCRIPTION";
     `P "lvcreate creates a new logical volume in a volume group by allocating logical extents from the free physical extent pool of that volume group.  If there are not enough free physical extents then the volume group can be extended with other physical volumes or by reducing existing logical volumes of this volume group in size."
   ] in
-  Term.(pure lvcreate $ Xenvm_common.copts_t $ lv_name_arg $ Xenvm_common.real_size_arg $ Xenvm_common.percent_size_arg $ tags_arg $ vg_name_arg),
+  Term.(pure lvcreate $ Xenvm_common.copts_t $ lv_name_arg $ Xenvm_common.real_size_arg $ Xenvm_common.percent_size_arg $ tags_arg $ vg_name_arg $ Xenvm_common.action_arg),
   Term.info "lvcreate" ~sdocs:"COMMON OPTIONS" ~doc ~man
 
   
diff --git a/xenvm/xenvm.ml b/xenvm/xenvm.ml
index 0d8d81e..d302b38 100644
--- a/xenvm/xenvm.ml
+++ b/xenvm/xenvm.ml
@@ -79,6 +79,30 @@ let format config name filenames =
       return () in
   Lwt_main.run t
 
+let dump config filenames =
+    let t =
+      let module Vg_IO = Vg.Make(Log)(Block)(Time)(Clock) in
+      let open Xenvm_interface in
+      Lwt_list.map_s
+        (fun filename ->
+          Block.connect filename
+          >>= function
+          | `Error _ -> fail (Failure (Printf.sprintf "Failed to open %s" filename))
+          | `Ok x -> return x
+        ) filenames
+      >>= fun blocks ->
+      Vg_IO.connect blocks `RO
+      >>|= fun vg ->
+      let md = Vg_IO.metadata_of vg in
+      let buf = Cstruct.create (64 * 1024 * 1024) in
+      let next = Vg.marshal md buf in
+      let buf = Cstruct.(sub buf 0 ((len buf) - (len next))) in
+      let txt = Cstruct.to_string buf in
+      output_string Pervasives.stdout txt;
+      output_string Pervasives.stdout "\n";
+      return () in
+  Lwt_main.run t
+
 let host_create copts (vg_name,_) host =
   let t =
     get_vg_info_t copts vg_name >>= fun info ->
@@ -140,37 +164,79 @@ let shutdown copts (vg_name,_) =
     lwt_while (fun () -> is_alive pid) (fun () -> Lwt_unix.sleep 1.0)
   in Lwt_main.run t
 
-let benchmark copts (vg_name,_) =
+let benchmark copts (vg_name,_) volumes threads =
   let t =
     let creation_host = Unix.gethostname () in
     get_vg_info_t copts vg_name >>= fun info ->
     set_uri copts info;
     let mib = Int64.mul 1048576L 4L in
-    let number = 1000 in
-    let start = Unix.gettimeofday () in
-    let rec fori test_name acc f = function
-    | 0 -> return acc
-    | n ->
-      f n
-      >>= fun () ->
-      ( if ((n * 100) / number) <> (((n + 1) * 100) / number)
-        then stderr "%s %d %% complete\n%!" test_name (100 - (n * 100) / number)
-        else return () ) >>= fun () ->
-      fori test_name ((number - n, Unix.gettimeofday () -. start) :: acc) f (n - 1) in
-    fori "Creating volumes" [] (fun i -> Client.create ~name:(Printf.sprintf "test-lv-%d" i) ~size:mib ~creation_host ~creation_time:(Unix.gettimeofday () |> Int64.of_float) ~tags:[]) number
-    >>= fun creates ->
-    let time = Unix.gettimeofday () -. start in
+
+    let start = ref (Unix.gettimeofday ()) in
+    let n_pending = ref volumes in
+    let m = Lwt_mutex.create () in
+    let n_complete = ref 0 in
+    let times = ref [] in
+    let on_complete () =
+      incr n_complete;
+      let n = !n_complete in
+      times := (n, Unix.gettimeofday () -. !start) :: !times;
+      if ((n * 100) / volumes) <> (((n + 1) * 100) / volumes)
+      then stderr "%d %% complete" ((n * 100) / volumes)
+      else return () in
+    let rec worker f =
+      Lwt_mutex.with_lock m
+        (fun () ->
+          if !n_pending > 0 then begin
+            decr n_pending;
+            return (Some (volumes - !n_pending))
+          end else return None)
+      >>= function
+      | Some n ->
+        f n
+        >>= fun () ->
+        on_complete ()
+        >>= fun () ->
+        worker f
+      | None ->
+        return () in
+
+    let create n =
+      Client.create ~name:(Printf.sprintf "test-lv-%d" n) ~size:mib ~creation_host ~creation_time:(Unix.gettimeofday () |> Int64.of_float) ~tags:[] in
+    let destroy n =
+      Client.remove ~name:(Printf.sprintf "test-lv-%d" n) in
+
+    let rec mkints = function
+      | 0 -> []
+      | n -> n :: (mkints (n - 1)) in
+    let creators = List.map (fun _ -> worker create) (mkints threads) in
+    Lwt.join creators
+    >>= fun () ->
+
     let oc = open_out "benchmark.dat" in
-    List.iter (fun (n, t) -> Printf.fprintf oc "%d %f\n" n t) (List.rev creates);
-    Printf.fprintf oc "# %d creates in %.1f s\n" number time;
-    Printf.fprintf oc "# Average %.1f /sec\n" (float_of_int number /. time);
-    let start = Unix.gettimeofday () in
-    fori "Removing volumes" [] (fun i -> Client.remove ~name:(Printf.sprintf "test-lv-%d" i)) number
-    >>= fun destroys ->
-    let time = Unix.gettimeofday () -. start in
-    List.iter (fun (n, t) -> Printf.fprintf oc "%d %f\n" (number + n) t) (List.rev destroys);
-    Printf.fprintf oc "# %d destroys in %.1f s\n" number time;
-    Printf.fprintf oc "# Average %.1f /sec\n" (float_of_int number /. time);
+    let time = Unix.gettimeofday () -. !start in
+    List.iter (fun (n, t) -> Printf.fprintf oc "%d %f\n" n t) (List.rev !times);
+    Printf.fprintf oc "# %d creates in %.1f s\n" volumes time;
+    Printf.fprintf oc "# Average %.1f /sec\n" (float_of_int volumes /. time);
+
+    start := Unix.gettimeofday ();
+    n_pending := volumes;
+    n_complete := 0;
+    times := [];
+
+    let destroyers = List.map (fun _ -> worker destroy) (mkints threads) in
+    Lwt.join destroyers
+    >>= fun () ->
+    let time = Unix.gettimeofday () -. !start in
+    List.iter (fun (n, t) -> Printf.fprintf oc "%d %f\n" (volumes + n) t) (List.rev !times);
+    Printf.fprintf oc "# %d destroys in %.1f s\n" volumes time;
+    Printf.fprintf oc "# Average %.1f /sec\n" (float_of_int volumes /. time);
+    close_out oc;
+    let oc = open_out "benchmark.gp" in
+    Printf.fprintf oc "set xlabel \"LV number\"\n";
+    Printf.fprintf oc "set ylabel \"Time/seconds\"\n";
+    Printf.fprintf oc "set title \"Creating and then destroying %d LVs\"\n" volumes;
+    Printf.fprintf oc "plot \"benchmark.dat\" with points\n";
+    close_out oc;
     return () in
   Lwt_main.run t
 
@@ -213,6 +279,15 @@ let size =
   let doc = "Size of the LV in megs" in
   Arg.(value & opt int64 4L & info ["size"] ~docv:"SIZE" ~doc)
 
+let dump_cmd =
+  let doc = "Dump the metadata in LVM format to stdout" in
+  let man = [
+    `S "DESCRIPTION";
+    `P "Prints the volume group metadata to stdout in LVM format. Note this will not include any updates which are still pending in the redo-log."
+  ] in
+  Term.(pure dump $ copts_t $ filenames),
+  Term.info "dump" ~sdocs:copts_sect ~doc ~man
+
 let format_cmd =
   let doc = "Format the specified file as a VG" in
   let man = [
@@ -282,7 +357,13 @@ let benchmark_cmd =
     `S "DESCRIPTION";
     `P "Perform some microbenchmarks and print the results.";
   ] in
-  Term.(pure benchmark $ copts_t $ name_arg),
+  let volumes_arg =
+    let doc = "The number of logical volumes which should be created then destroyed." in
+    Arg.(value & opt int 10000 & info [ "volumes"; "v" ] ~docv:"VOLUMES" ~doc) in
+  let threads_arg =
+    let doc = "The number of concurrent worker threads which should create then destroy the volumes." in
+    Arg.(value & opt int 1 & info [ "threads"; "t" ] ~docv:"THREADS" ~doc) in
+  Term.(pure benchmark $ copts_t $ name_arg $ volumes_arg $ threads_arg),
   Term.info "benchmark" ~sdocs:copts_sect ~doc ~man
 
 let default_cmd =
@@ -292,6 +373,7 @@ let cmds = [
   Lvresize.lvresize_cmd;
   Lvresize.lvextend_cmd;
   format_cmd;
+  dump_cmd;
   shutdown_cmd; host_create_cmd; host_destroy_cmd;
   host_list_cmd;
   host_connect_cmd; host_disconnect_cmd; benchmark_cmd;