/*
* 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.cassandra.tools.nodetool;
import org.apache.cassandra.tools.NodeProbe;
import org.apache.cassandra.tools.NodeTool.NodeToolCmd;
import io.airlift.command.Command;
@Command(name = "gcstats", description = "Print GC Statistics")
public class GcStats extends NodeToolCmd
{
@Override
public void execute(NodeProbe probe)
{
double[] stats = probe.getAndResetGCStats();
double mean = stats[2] / stats[5];
double stdev = Math.sqrt((stats[3] / stats[5]) - (mean * mean));
System.out.printf("%20s%20s%20s%20s%20s%20s%25s%n", "Interval (ms)", "Max GC Elapsed (ms)", "Total GC Elapsed (ms)", "Stdev GC Elapsed (ms)", "GC Reclaimed (MB)", "Collections", "Direct Memory Bytes");
System.out.printf("%20.0f%20.0f%20.0f%20.0f%20.0f%20.0f%25d%n", stats[0], stats[1], stats[2], stdev, stats[4], stats[5], (long)stats[6]);
}
}