diff --git a/src/main/frontend/fs/sync.cljs b/src/main/frontend/fs/sync.cljs
index bed4088c7..153469d98 100644
--- a/src/main/frontend/fs/sync.cljs
+++ b/src/main/frontend/fs/sync.cljs
@@ -1050,18 +1050,9 @@
 
 ;;; ### sync events
 
-;; "`SyncManager` will put some internal sync events to this chan.
-;;   see also spec `::sync-event`"
-(defonce ^:private sync-events-chan
-  (chan (async/sliding-buffer 1000)))
-;; see also spec `::event` for topic list
-(defonce sync-events-publication
-  (async/pub sync-events-chan :event))
-
 (defn- put-sync-event!
   [val]
-  {:pre [(s/valid? ::sync-event val)]}
-  (async/put! sync-events-chan val))
+  (async/put! pubsub/sync-events-ch val))
 
 (def ^:private debug-print-sync-events-loop-stop-chan (chan 1))
 (defn debug-print-sync-events-loop
@@ -1079,7 +1070,7 @@
          out-ch (chan 10)
          out-mix (async/mix out-ch)]
      (doseq [[topic ch] topic&chs]
-       (async/sub sync-events-publication topic ch)
+       (async/sub pubsub/sync-events-pub topic ch)
        (async/admix out-mix ch))
      (go-loop []
        (let [{:keys [val stop]}
@@ -1089,7 +1080,7 @@
          (cond
            stop (do (async/unmix-all out-mix)
                     (doseq [[topic ch] topic&chs]
-                      (async/unsub sync-events-publication topic ch)))
+                      (async/unsub pubsub/sync-events-pub topic ch)))
 
            val (do (pp/pprint [:debug :sync-event val])
                    (recur))))))))
@@ -1100,30 +1091,6 @@
   (offer! debug-print-sync-events-loop-stop-chan true))
 
 
-(comment
- ;; sub one type event example:
- (def c1 (chan 10))
- (async/sub sync-events-publication :created-local-version-file c1)
- (offer! sync-events-chan {:event :created-local-version-file :data :xxx})
- (poll! c1)
-
- ;; sub multiple type events example:
- ;; sub :created-local-version-file and :finished-remote->local events,
- ;; output into channel c4-out
- (def c2 (chan 10))
- (def c3 (chan 10))
- (def c4-out (chan 10))
- (def mix-out (async/mix c4-out))
- (async/admix mix-out c2)
- (async/admix mix-out c3)
- (async/sub sync-events-publication :created-local-version-file c2)
- (async/sub sync-events-publication :finished-remote->local c3)
- (offer! sync-events-chan {:event :created-local-version-file :data :xxx})
- (offer! sync-events-chan {:event :finished-remote->local :data :xxx})
- (poll! c4-out)
- (poll! c4-out)
- )
-
 ;;; sync events ends
 
 (defn- fire-file-sync-storage-exceed-limit-event!
@@ -3316,7 +3283,7 @@
 
 ;; re-exec remote->local-full-sync when it failed before
 (def re-remote->local-full-sync-chan (chan 1))
-(async/sub sync-events-publication :remote->local-full-sync-failed re-remote->local-full-sync-chan)
+(async/sub pubsub/sync-events-pub :remote->local-full-sync-failed re-remote->local-full-sync-chan)
 (go-loop []
   (let [{{graph-uuid :graph-uuid} :data} (<! re-remote->local-full-sync-chan)
         {:keys [current-syncing-graph-uuid]}
@@ -3327,7 +3294,7 @@
 
 ;; re-exec local->remote-full-sync when it failed
 (def re-local->remote-full-sync-chan (chan 1))
-(async/sub sync-events-publication :local->remote-full-sync-failed re-local->remote-full-sync-chan)
+(async/sub pubsub/sync-events-pub :local->remote-full-sync-failed re-local->remote-full-sync-chan)
 (go-loop []
   (let [{{graph-uuid :graph-uuid} :data} (<! re-local->remote-full-sync-chan)
         {:keys [current-syncing-graph-uuid]} (state/get-file-sync-state graph-uuid)]
diff --git a/src/main/frontend/handler/file_sync.cljs b/src/main/frontend/handler/file_sync.cljs
index 1c4b8ab9d..7ea76c1c4 100644
--- a/src/main/frontend/handler/file_sync.cljs
+++ b/src/main/frontend/handler/file_sync.cljs
@@ -12,6 +12,7 @@
             [frontend.state :as state]
             [frontend.handler.user :as user]
             [frontend.fs :as fs]
+            [frontend.pubsub :as pubsub]
             [cljs-time.coerce :as tc]
             [cljs-time.core :as t]
             [frontend.storage :as storage]
@@ -197,7 +198,7 @@
 (defn setup-file-sync-event-listeners
   []
   (let [c     (async/chan 1)
-        p     sync/sync-events-publication
+        p     pubsub/sync-events-pub
         topics [:finished-local->remote :finished-remote->local :start]]
     (doseq [topic topics]
       (async/sub p topic c))
diff --git a/src/main/frontend/pubsub.cljc b/src/main/frontend/pubsub.cljc
index 5063ce5f8..0540dc0fd 100644
--- a/src/main/frontend/pubsub.cljc
+++ b/src/main/frontend/pubsub.cljc
@@ -72,4 +72,5 @@
             :get-remote-graph-failed
             :get-deletion-logs-failed]]
    [:data :map]]
-  :topic-fn :event)
+  :topic-fn :event
+  :ch-buffer (a/sliding-buffer 10))