diff --git a/services/appmgr/src/cgroup_manager.cpp b/services/appmgr/src/cgroup_manager.cpp
index aeb33bfaf2d2ef25f7bacd597f23a257c772ddff..886961a9d43a4cc2159702e7798dafa652e9f27a 100644
--- a/services/appmgr/src/cgroup_manager.cpp
+++ b/services/appmgr/src/cgroup_manager.cpp
@@ -310,8 +310,8 @@ void CgroupManager::OnReadable(int32_t fd)
 {
     APP_LOGW("system low memory alert.");
 
-    if (!LowMemoryAlert || LowMemoryAlert) {
-        APP_LOGW("OnReadable 'LowMemoryAlert' come.");
+    if (!LowMemoryAlert) {
+        APP_LOGW("'LowMemoryAlert' not available.");
         return;
     }
 
diff --git a/services/appmgr/src/process_optimizer.cpp b/services/appmgr/src/process_optimizer.cpp
index 3af3f1c3d8062e3f7acaeb6e1bb31e8413ab4419..534f4cd5df5ef3a33d34a0a6106f08d85d64d772 100644
--- a/services/appmgr/src/process_optimizer.cpp
+++ b/services/appmgr/src/process_optimizer.cpp
@@ -78,6 +78,8 @@ ProcessOptimizer::ProcessOptimizer(const LmksClientPtr &lmksClient, int suspendT
 
 ProcessOptimizer::~ProcessOptimizer()
 {
+    APP_LOGI("ProcessOptimizer destructed");
+    DelayedSingleton<CgroupManager>::GetInstance()->LowMemoryAlert = nullptr;
     if (lmksClient_) {
         lmksClient_->ProcPurge();
     }