Offloader metrics (apache#13833)

### Motivation
Currently, there is no offload metrics for tiered storage, so it is very hard for us to debug the performance issues. For example , we can not find why offload is slow or why read offload is slow. For above reasons. we need to add some offload metrics for monitoring.

### Modifications
Add metrics during offload procedure and read offload data procedure. Including offloadTime, offloadError, offloadRate, readLedgerLatency, writeStoreLatency, writeStoreError, readOffloadIndexLatency, readOffloadDataLatency, readOffloadRate, readOffloadError.

managed-ledger/src/main/java/org/apache/bookkeeper/mledger/LedgerOffloaderFactory.java

@@ -52,7 +52,8 @@ public interface LedgerOffloaderFactory<T extends LedgerOffloader> {
      */
     T create(OffloadPoliciesImpl offloadPolicies,
              Map<String, String> userMetadata,
-             OrderedScheduler scheduler)
+             OrderedScheduler scheduler,
+             LedgerOffloaderStats offloaderStats)
         throws IOException;
 
     /**
@@ -68,8 +69,9 @@ T create(OffloadPoliciesImpl offloadPolicies,
     default T create(OffloadPoliciesImpl offloadPolicies,
                      Map<String, String> userMetadata,
                      SchemaStorage schemaStorage,
-                     OrderedScheduler scheduler)
+                     OrderedScheduler scheduler,
+                     LedgerOffloaderStats offloaderStats)
             throws IOException {
-        return create(offloadPolicies, userMetadata, scheduler);
+        return create(offloadPolicies, userMetadata, scheduler, offloaderStats);
     }
 }

managed-ledger/src/main/java/org/apache/bookkeeper/mledger/LedgerOffloaderStats.java

@@ -0,0 +1,62 @@
+/**
+ * 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.bookkeeper.mledger;
+
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import org.apache.bookkeeper.common.annotation.InterfaceAudience;
+import org.apache.bookkeeper.common.annotation.InterfaceStability;
+import org.apache.bookkeeper.mledger.impl.LedgerOffloaderStatsImpl;
+
+
+/**
+ * Management Bean for a {@link LedgerOffloader}.
+ */
+@InterfaceAudience.LimitedPrivate
+@InterfaceStability.Stable
+public interface LedgerOffloaderStats extends AutoCloseable {
+
+    void recordOffloadError(String topic);
+
+    void recordOffloadBytes(String topic, long size);
+
+    void recordReadLedgerLatency(String topic, long latency, TimeUnit unit);
+
+    void recordWriteToStorageError(String topic);
+
+    void recordReadOffloadError(String topic);
+
+    void recordReadOffloadBytes(String topic, long size);
+
+    void recordReadOffloadIndexLatency(String topic, long latency, TimeUnit unit);
+
+    void recordReadOffloadDataLatency(String topic, long latency, TimeUnit unit);
+
+    void recordDeleteOffloadOps(String topic, boolean succeed);
+
+
+    static LedgerOffloaderStats create(boolean exposeManagedLedgerStats, boolean exposeTopicLevelMetrics,
+                                       ScheduledExecutorService scheduler, int interval) {
+        if (!exposeManagedLedgerStats) {
+            return LedgerOffloaderStatsDisable.INSTANCE;
+        }
+
+        return LedgerOffloaderStatsImpl.getInstance(exposeTopicLevelMetrics, scheduler, interval);
+    }
+}

managed-ledger/src/main/java/org/apache/bookkeeper/mledger/LedgerOffloaderStatsDisable.java

@@ -0,0 +1,80 @@
+/**
+ * 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.bookkeeper.mledger;
+
+import java.util.concurrent.TimeUnit;
+
+class LedgerOffloaderStatsDisable implements LedgerOffloaderStats {
+
+    static final LedgerOffloaderStats INSTANCE = new LedgerOffloaderStatsDisable();
+
+    private LedgerOffloaderStatsDisable() {
+
+    }
+
+    @Override
+    public void recordOffloadError(String topic) {
+
+    }
+
+    @Override
+    public void recordOffloadBytes(String topic, long size) {
+
+    }
+
+    @Override
+    public void recordReadLedgerLatency(String topic, long latency, TimeUnit unit) {
+
+    }
+
+    @Override
+    public void recordWriteToStorageError(String topic) {
+
+    }
+
+    @Override
+    public void recordReadOffloadError(String topic) {
+
+    }
+
+    @Override
+    public void recordReadOffloadBytes(String topic, long size) {
+
+    }
+
+    @Override
+    public void recordReadOffloadIndexLatency(String topic, long latency, TimeUnit unit) {
+
+    }
+
+    @Override
+    public void recordReadOffloadDataLatency(String topic, long latency, TimeUnit unit) {
+
+    }
+
+    @Override
+    public void recordDeleteOffloadOps(String topic, boolean succeed) {
+
+    }
+
+    @Override
+    public void close() throws Exception {
+
+    }
+}