Merge pull request #5976 from GabrielBuica/private/dbuica/CP-50723-se…

…t-last-active

CP-51352: Compare before setting a new value for `last_active`

ocaml/xapi/session_check.ml

@@ -53,9 +53,34 @@ let check ~intra_pool_only ~session_id ~action =
           if (not pool) && not (Pool_role.is_master ()) then
             raise Non_master_login_on_slave ;
           if Pool_role.is_master () then
-            Db_actions.DB_Action.Session.set_last_active ~__context
-              ~self:session_id
-              ~value:(Xapi_stdext_date.Date.of_float (Unix.time ()))
+            (* before updating the last_active field, check if the field has been
+               already updated recently. This avoids holding the database lock too often.*)
+            let n = Xapi_stdext_date.Date.now () in
+            let last_active =
+              Db_actions.DB_Action.Session.get_last_active ~__context
+                ~self:session_id
+            in
+            let ptime_now = Xapi_stdext_date.Date.to_ptime n in
+            let refresh_threshold =
+              let last_active_ptime =
+                Xapi_stdext_date.Date.to_ptime last_active
+              in
+              match
+                Ptime.add_span last_active_ptime
+                  !Xapi_globs.threshold_last_active
+              with
+              | None ->
+                  let err_msg =
+                    "Can't add the configurable threshold of last active to \
+                     the current time."
+                  in
+                  raise Api_errors.(Server_error (internal_error, [err_msg]))
+              | Some ptime ->
+                  ptime
+            in
+            if Ptime.is_later ptime_now ~than:refresh_threshold then
+              Db_actions.DB_Action.Session.set_last_active ~__context
+                ~self:session_id ~value:n
         with
         | Db_exn.DBCache_NotFound (_, _, reference) ->
             info

ocaml/xapi/xapi_globs.ml

@@ -712,6 +712,10 @@ let host_assumed_dead_interval = ref Mtime.Span.(10 * min)
 (* If a session has a last_active older than this we delete it *)
 let inactive_session_timeout = ref 86400. (* 24 hrs in seconds *)
 
+(* If a session was refreshed more recently than threshold_last_active do not refresh it again. *)
+let threshold_last_active = ref (Ptime.Span.of_int_s 600)
+(* 10 min in seconds *)
+
 let pending_task_timeout = ref 86400. (* 24 hrs in seconds *)
 
 let completed_task_timeout = ref 3900. (* 65 mins *)
@@ -1631,6 +1635,11 @@ let other_options =
     , (fun () -> string_of_int !external_authentication_cache_size)
     , "Specify the maximum capacity of the external authentication cache"
     )
+  ; ( "threshold_last_active"
+    , Arg.Int (fun t -> threshold_last_active := Ptime.Span.of_int_s t)
+    , (fun () -> Format.asprintf "%a" Ptime.Span.pp !threshold_last_active)
+    , "Specify the threshold below which we do not refresh the session"
+    )
   ]
 
 (* The options can be set with the variable xapiflags in /etc/sysconfig/xapi.