Github user sihuazhou commented on a diff in the pull request:
https://github.com/apache/flink/pull/6186#discussion_r197004891
--- Diff:
flink-runtime/src/main/java/org/apache/flink/runtime/state/ttl/TtlValue.java ---
@@ -0,0 +1,47 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.runtime.state.ttl;
+
+import org.apache.flink.util.Preconditions;
+
+import java.io.Serializable;
+
+/**
+ * This class wraps user value of state with TTL.
+ *
+ * @param <T> Type of the user value of state with TTL
+ */
+class TtlValue<T> implements Serializable {
+ private final T userValue;
+ private final long expirationTimestamp;
--- End diff --
The `expirationTimestamp` is an absolute timestamp, should we do the
timestamp shift for `TtlValue` when checkpoint & recovery? For example, when
user using the `ProcessTime` as the TimeCharacater, and set the `TTL = 10min`.
For some reason, he triggers a savepoint, and after 11 min he recover the job
from the savepoint, if we don't do the timestamp shift, then all the state will
be expired.
---