diff --git a/src/ipc.cpp b/src/ipc.cpp
index cd15a88..6731ba5 100755
--- a/src/ipc.cpp
+++ b/src/ipc.cpp
@@ -555,7 +555,7 @@ static ipc::buff_t recv(ipc::handle_t h, std::size_t tm) {
                         recycle_storage(reinterpret_cast<std::size_t>(ptr) - 1, size);
                     }, reinterpret_cast<void*>(buf_id + 1) };
                 }
-                else ipc::log("fail: shm::handle for big message. msg_id: %zd, size: %zd\n", msg.id_, remain);
+                else ipc::log("fail: shm::handle for big message. msg_id: %zd, buf_id: %zd, size: %zd\n", msg.id_, buf_id, remain);
             }
             // gc
             if (rc.size() > 1024) {
diff --git a/src/libipc/prod_cons.h b/src/libipc/prod_cons.h
index 735abbc..d5684fa 100755
--- a/src/libipc/prod_cons.h
+++ b/src/libipc/prod_cons.h
@@ -376,9 +376,14 @@ struct prod_cons_impl<wr<relat::multi, relat::multi, trans::broadcast>> {
             }
             // just compare & exchange
             if (el->rc_.compare_exchange_weak(
-                        cur_rc, inc_mask(epoch | (cur_rc & ep_mask)) | static_cast<rc_t>(cc), std::memory_order_relaxed) &&
-                epoch_.compare_exchange_weak(epoch, epoch, std::memory_order_acq_rel)) {
-                break;
+                        cur_rc, inc_mask(epoch | (cur_rc & ep_mask)) | static_cast<rc_t>(cc), std::memory_order_relaxed)) {
+                if (epoch == epoch_.load(std::memory_order_acquire)) {
+                    break;
+                }
+                else if (push(wrapper, std::forward<F>(f), elems)) {
+                    return true;
+                }
+                epoch = epoch_.fetch_add(ep_incr, std::memory_order_release) + ep_incr;
             }
             ipc::yield(k);
         }
diff --git a/src/libipc/waiter_helper.h b/src/libipc/waiter_helper.h
index ed267b6..a32035b 100644
--- a/src/libipc/waiter_helper.h
+++ b/src/libipc/waiter_helper.h
@@ -55,7 +55,7 @@ struct waiter_helper {
             }
             else if (flags.need_dest_.exchange(false, std::memory_order_release)) {
                 ret = false;
-                ctrl.sema_wait(tm);
+                ctrl.sema_wait(default_timeout);
                 break;
             }
             else {
@@ -106,6 +106,7 @@ struct waiter_helper {
     template <typename Ctrl>
     static bool quit_waiting(Ctrl & ctrl) {
         auto & flags = ctrl.flags();
+        flags.need_dest_.store(true, std::memory_order_relaxed);
         if (!flags.is_waiting_.exchange(false, std::memory_order_release)) {
             return true;
         }
@@ -116,7 +117,6 @@ struct waiter_helper {
         bool ret = true;
         IPC_UNUSED_ auto guard = ctrl.get_lock();
         if (counter.counter_ > 0) {
-            flags.need_dest_.store(true, std::memory_order_relaxed);
             ret = ctrl.sema_post(counter.counter_);
             counter.counter_ -= 1;
             ret = ret && ctrl.handshake_wait(default_timeout);