Package org.apache.hadoop.hbase.client.metrics

Class ServerSideScanMetrics

java.lang.Object

org.apache.hadoop.hbase.client.metrics.ServerSideScanMetrics

Direct Known Subclasses:

ScanMetrics

@Public
public class ServerSideScanMetrics
extends Object

Provides server side metrics related to scan operations.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	BLOCK_BYTES_SCANNED_KEY_METRIC_NAME
static final String	COUNT_OF_ROWS_FILTERED_KEY_METRIC_NAME
static final String	COUNT_OF_ROWS_SCANNED_KEY_METRIC_NAME
private final Map<String,AtomicLong>	counters	Hash to hold the String -> Atomic Long mappings for each metric
final AtomicLong	countOfBlockBytesScanned
final AtomicLong	countOfRowsFiltered	number of rows filtered during scan RPC
final AtomicLong	countOfRowsScanned	number of rows scanned during scan RPC.
protected RegionScanMetricsData	currentRegionScanMetricsData
static final String	FS_READ_TIME_METRIC_NAME
final AtomicLong	fsReadTime
private final List<RegionScanMetricsData>	regionScanMetricsData

Constructor Summary

Constructors

Constructor	Description
ServerSideScanMetrics()

Method Summary

Modifier and Type	Method	Description
void	addToCounter(String counterName, long delta)	Increments the counter with counterName by delta, does nothing if counter does not exist.
Map<ScanMetricsRegionInfo,Map<String,Long>>	collectMetricsByRegion()	Get values grouped by each region scanned since the last time this was called.
Map<ScanMetricsRegionInfo,Map<String,Long>>	collectMetricsByRegion(boolean reset)	Get values grouped by each region scanned.
protected AtomicLong	createCounter(String counterName)	Create a new counter with the specified name.
AtomicLong	getCounter(String counterName)	Returns AtomicLong instance for this counter name, null if counter does not exist.
Map<String,Long>	getMetricsMap()	Get all the values combined for all the regions since the last time this function was called.
Map<String,Long>	getMetricsMap(boolean reset)	Get all the values combined for all the regions.
boolean	hasCounter(String counterName)	Returns true if a counter exists with the counterName.
void	initScanMetricsRegionInfo(String encodedRegionName, ServerName serverName)	Call this method after calling moveToNextRegion() to populate server name and encoded region name details for the region being scanned and for which metrics are being collected at the moment.
void	moveToNextRegion()	If region level scan metrics are enabled, must call this method to start collecting metrics for the region before scanning the region.
void	setCounter(String counterName, long value)	Sets counter with counterName to passed in value, does nothing if counter does not exist.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

counters

private final Map<String,AtomicLong> counters

Hash to hold the String -> Atomic Long mappings for each metric

regionScanMetricsData

private final List<RegionScanMetricsData> regionScanMetricsData

currentRegionScanMetricsData

protected RegionScanMetricsData currentRegionScanMetricsData

COUNT_OF_ROWS_SCANNED_KEY_METRIC_NAME

public static final String COUNT_OF_ROWS_SCANNED_KEY_METRIC_NAME

See Also:

• Constant Field Values

COUNT_OF_ROWS_FILTERED_KEY_METRIC_NAME

public static final String COUNT_OF_ROWS_FILTERED_KEY_METRIC_NAME

See Also:

• Constant Field Values

BLOCK_BYTES_SCANNED_KEY_METRIC_NAME

public static final String BLOCK_BYTES_SCANNED_KEY_METRIC_NAME

See Also:

• Constant Field Values

FS_READ_TIME_METRIC_NAME

public static final String FS_READ_TIME_METRIC_NAME

See Also:

• Constant Field Values

countOfRowsFiltered

public final AtomicLong countOfRowsFiltered

number of rows filtered during scan RPC

countOfRowsScanned

public final AtomicLong countOfRowsScanned

number of rows scanned during scan RPC. Not every row scanned will be returned to the client since rows may be filtered.

countOfBlockBytesScanned

public final AtomicLong countOfBlockBytesScanned

fsReadTime

public final AtomicLong fsReadTime

Constructor Details

ServerSideScanMetrics

public ServerSideScanMetrics()

Method Details

moveToNextRegion

public void moveToNextRegion()

If region level scan metrics are enabled, must call this method to start collecting metrics for the region before scanning the region.

createCounter

protected AtomicLong createCounter(String counterName)

Create a new counter with the specified name.

Returns:

AtomicLong instance for the counter with counterName

setCounter

public void setCounter(String counterName,
 long value)

Sets counter with counterName to passed in value, does nothing if counter does not exist. If region level scan metrics are enabled then sets the value of counter for the current region being scanned.

hasCounter

public boolean hasCounter(String counterName)

Returns true if a counter exists with the counterName.

getCounter

public AtomicLong getCounter(String counterName)

Returns AtomicLong instance for this counter name, null if counter does not exist.

addToCounter

public void addToCounter(String counterName,
 long delta)

Increments the counter with counterName by delta, does nothing if counter does not exist. If region level scan metrics are enabled then increments the counter corresponding to the current region being scanned. Please see moveToNextRegion().

getMetricsMap

public Map<String,Long> getMetricsMap()

Get all the values combined for all the regions since the last time this function was called. Calling this function will reset all AtomicLongs in the instance back to 0.

Returns:

A Map of String -> Long for metrics

getMetricsMap

public Map<String,Long> getMetricsMap(boolean reset)

Get all the values combined for all the regions. If reset is true, we will reset all the AtomicLongs back to 0.

Parameters:

reset - whether to reset the AtomicLongs to 0.

Returns:

A Map of String -> Long for metrics

collectMetricsByRegion

public Map<ScanMetricsRegionInfo,Map<String,Long>> collectMetricsByRegion()

Get values grouped by each region scanned since the last time this was called. Calling this function will reset all region level scan metrics counters back to 0.

Returns:

A Map of region -> (Map of metric name -> Long) for metrics

collectMetricsByRegion

public Map<ScanMetricsRegionInfo,Map<String,Long>> collectMetricsByRegion(boolean reset)

Get values grouped by each region scanned. If reset is true, will reset all the region level scan metrics counters back to 0.

Parameters:

reset - whether to reset region level scan metric counters to 0.

Returns:

A Map of region -> (Map of metric name -> Long) for metrics

toString

public String toString()

Overrides:

toString in class Object

initScanMetricsRegionInfo

public void initScanMetricsRegionInfo(String encodedRegionName,
 ServerName serverName)

Call this method after calling moveToNextRegion() to populate server name and encoded region name details for the region being scanned and for which metrics are being collected at the moment.