gmetric -c /etc/gmond.conf --name="My Metric" --value="My Value" --type="float" --units="My Unit"

Combined with the disk monitor tool iostat, gmetric allows to measure disk metrics.

Linux 2.6.18-274.17.1.el5xen       04/19/2012

Device:         rrqm/s   wrqm/s   r/s   w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await  svctm  %util
xvda              2.28    32.11 26.13 14.69   812.28   187.20    48.97     0.96   23.58   2.80  11.42
xvda1             0.00     0.00  0.00  0.00     0.00     0.00     7.82     0.00   45.52  30.23   0.00
xvda2             0.37     6.46  5.22  4.91   127.79    45.47    34.22     0.24   24.13   4.06   4.11
xvda3             1.38     7.29 15.68  3.96   490.93    45.01    54.56     0.33   16.84   3.30   6.47
xvda4             0.53    18.36  5.24  5.81   193.56    96.72    52.54     0.39   35.07   2.04   2.25
xvdb              0.87    15.35 11.04  8.91   316.92    97.04    41.50     0.49   24.52   3.10   6.18
xvdb1             0.87    15.35 11.04  8.91   316.92    97.04    41.50     0.49   24.52   3.10   6.18
dm-0              0.00     0.00 40.33 71.06  1129.20   284.24    25.38     0.73    6.51   1.50  16.66
dm-1              0.00     0.00  0.00  0.00     0.00     0.00     8.00     0.00   16.82   1.54   0.00

So i wrote I small PHP script which puts the iostat data to gmetric and is called periodically by a cronjob.

exec('iostat -d -x -k 10 2', $out);

	$out = array_slice($out, ceil(count($out)/2));

	//var_dump($out);
	$header = array();
	$data = array();

	foreach($out as $line)
	{
		$line= preg_replace('/\s+/', ' ',$line);
		$cols = explode(" ", $line);

		if($cols[0] == "Device:"){
			$header = $cols;
		}elseif(count($header) > 0 && count($cols) > 1){
			$data[] = $cols;
		}

	}

	$units = array();
	$units['rrqm_s'] = 'Queued Requests/s';
	$units['wrqm_s'] = 'Queued Requests/s';
	$units['r_s'] =  'Requests/s';
	$units['w_s'] =  'Requests/s';
	$units['rkB_s'] = 'kB/s';
	$units['wkB_s'] = 'kB/s';
	$units['avgrq-sz'] = 'Sectors';
	$units['avgqu-sz'] =  'Sectors';
	$units['await'] =  'ms';
	$units['svctm'] =  'ms';
	$units['util'] =  '%';

	//clean
	for($col=0;$col<count($header);$col++)
	{
		$header[$col] = str_replace("/", "_", $header[$col]);
		$header[$col] = str_replace("%", "", $header[$col]);
	}

	for($row=0;$row<count($data);$row++)
	{
		for($col=1;$col<count($header);$col++)
		{
			if($col != 5 && $col != 6 && $col != 11)
			continue;

			if($header[$col]=='')
			continue;

			if(!isset($data[$row][$col]))
			continue;

			$caption = "disk_".$data[$row][0]."-".$header[$col];
			$value = $data[$row][$col];
			$unit = $units[$header[$col]];

			//echo $caption."->".$value."\n";

			exec('gmetric -c /etc/gmond.conf --name="'.$caption.'" --value="'.$value.'" --type="float" --units="'.$unit.'"');
		}
	}

Using Ganglia Web 2 the outcome is pretty candy

function curl($URLServer,$postdata="", $cookieFile=null, $proxy=true, $proxyRetry=0)
{
		global $proxyCache;
		//sleep(20);
		$agent = "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.12) Gecko/20101027 Ubuntu/10.10 (maverick) Firefox/3.6.12";
		$cURL_Session = curl_init();
		 
		curl_setopt($cURL_Session, CURLOPT_URL,$URLServer);
		curl_setopt($cURL_Session, CURLOPT_USERAGENT, $agent);
		if($postdata != "")
		{
		curl_setopt($cURL_Session, CURLOPT_POST, 1);
		curl_setopt($cURL_Session, CURLOPT_POSTFIELDS,$postdata);
		}
		curl_setopt($cURL_Session, CURLOPT_RETURNTRANSFER, 1);
		//curl_setopt($cURL_Session, CURLOPT_FOLLOWLOCATION, 1);
		if($cookieFile != null){
		curl_setopt($cURL_Session,CURLOPT_COOKIEJAR, $cookieFile);
		curl_setopt($cURL_Session,CURLOPT_COOKIEFILE, $cookieFile);  
		}
		
		if($proxy == true)
		{
			if($proxyCache == "")
			{
			$c = curl("http://www.proxylist.net/", "", null, false);
			preg_match_all("/([0-9]*).([0-9]*).([0-9]*).([0-9]*):([0-9]*)/", $c, $matches);
			$matches = $matches[0];
			$proxyCache = $matches[rand(0, (count($matches)-1))];
			}
			
			echo "proxy:$proxyCache<br>";
			
						
			list($proxy_ip, $proxy_port) = explode(":", $proxyCache);

			curl_setopt($cURL_Session, CURLOPT_PROXYPORT, $proxy_port);
			curl_setopt($cURL_Session, CURLOPT_PROXYTYPE, 'HTTP');
			curl_setopt($cURL_Session, CURLOPT_PROXY, $proxy_ip);		
		}
		
		$result = curl_exec ($cURL_Session);
		
		if($result === false)
		{
    	echo 'Curl error: ' . curl_error($cURL_Session)."<br>";
    	
    	if($proxy == true && $proxyRetry <= 5)
    		curl($URLServer,$postdata="", $cookieFile, $proxy, $proxyRetry++);
		}
		curl_close ($cURL_Session);
		 
		return $result;
}

Those services are accessible via thrift a high performance protocol for back end services.

As building a client with thrift is not that easy I decided to put my HBase and Hive php thrift client packages online for others.

Links:
Hadoop
Hive
HBase
Thrift

How it works

Start the HBase and Hive Thrift server via shell:

hive --service hiveserver
/usr/lib/hbase/bin/hbase-daemon.sh start thrift

Download HBase and Thrift php client package and write your own client:

//thrift php
$GLOBALS['THRIFT_ROOT'] = dirname(__FILE__).'/thrift/src';
require_once( $GLOBALS['THRIFT_ROOT'].'/Thrift.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/transport/TSocket.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/transport/TBufferedTransport.php' );
require_once( $GLOBALS['THRIFT_ROOT'].'/protocol/TBinaryProtocol.php' );

//hbase thrift
require_once dirname(__FILE__).'/thrift/Hbase.php';

//hive thrift
require_once dirname(__FILE__).'/thrift/ThriftHive.php';

/*
HBase php thrift client
*/

//open connection
$socket = new TSocket( 'localhost', 9090 );
$transport = new TBufferedTransport( $socket );
$protocol = new TBinaryProtocol( $transport );
$client = new HbaseClient( $protocol );
$transport->open();

//show all tables
$tables = $client->getTableNames();
foreach ( $tables as $name ) {
echo( "  found: {$name}\n" );
}

//Create a table
try {
$columns = array(new ColumnDescriptor( array(
'name' =>; 'colFamily:',
'maxVersions' => 10) ));

$client->createTable("tableName", $columns );
} catch ( AlreadyExists $ae ) {
echo( "WARN: {$ae->;message}\n" );
}

//insert data to table
$mutations = array(
new Mutation( array(
'column' => 'colFamily:Col',
'value' => 'value123'
) ),
);
$client->mutateRow( "tableName", "ID_1237846634624", $mutations );

//get table data
$row = $client->getRow("tableName", "ID_1237846634624");

/*
Hive php thrift client
*/

//open connection
$transport = new TSocket("localhost", 10000);
$protocol = new TBinaryProtocol($transport);
$client = new ThriftHiveClient($protocol);
$transport->open();

//show tables
$client->execute('SHOW TABLES');
$tables = $client->fetchAll();
foreach ($tables as $name){
echo( " found: {$name}\n" );
}

//Create Hive table with Hbase table mapping
$mapping = 'CREATE EXTERNAL TABLE tableName(Col String, Col1 String)

STORED BY \'org.apache.hadoop.hive.hbase.HBaseStorageHandler\'
WITH SERDEPROPERTIES ("hbase.columns.mapping" = "colFamily:Col, colFamily:Col")
TBLPROPERTIES("hbase.table.name" = "tableName")';

$client->execute($mapping);

//Query table
$client->execute('SELECT * FROM tableName Limit 10');
var_dump($client->fetchAll());

Download source code

• Explores it’s environment while avoiding obstacles with an ultra sonar scanner and detects collisions with a bump sensor.
• Creates a map from cruising data and detected obstacles.
• Connects to bluetooth devices to exchange control data and commands.
• Is monitoring the surrounding area by decoding video data processing it with face detection
  and draw detected faces into the map
• Detects QR codes to receive commands and authentications.
• Uses text to speech.
• Serves a telnet interface for an interactive speech output.
• Implements a web interface for live image streams, log output and a real time map

Download