com.persistit.mxbeans

Interface IOMeterMXBean

@MXBean
public interface IOMeterMXBean

Manages statistics about various types of physical I/O operations. These are measures of I/O calls to the the file system and therefore only approximately represent the true volume of physical I/O operations.

Field Summary

Fields

Modifier and Type	Field and Description
static String	MXBEAN_NAME
static String[]	OPERATION_NAMES Abbreviated names for types of I/O operations measured by this bean: RV Read page from Volume RJ Read page from Journal CC Copy page from journal to volume WJ Write page from Journal TJ Write Transaction to Journal XX Other EVD Evict page from pool FJ Flush journal GP Get Page
static String[]	OPERATIONS
static String[]	SUMMARY_ITEMS

Method Summary

Modifier and Type	Method and Description
long	getIoRate()
String	getLogFile()
long	getQuiescentIOthreshold()
void	setLogFile(String toFile) Set the path for file into which IO events should be logged, or null to disable IO logging.
void	setQuiescentIOthreshold(long quiescentIO)
long	totalBytes(String operation)
long	totalOperations(String operation)

Field Detail

MXBEAN_NAME

static final String MXBEAN_NAME

See Also:

Constant Field Values

OPERATION_NAMES

static final String[] OPERATION_NAMES

Abbreviated names for types of I/O operations measured by this bean:

RV

Read page from Volume

RJ

Read page from Journal

CC

Copy page from journal to volume

WJ

Write page from Journal

TJ

Write Transaction to Journal

XX

Other

EV

D

Evict page from pool

FJ

Flush journal

GP

Get Page

OPERATIONS

static final String[] OPERATIONS

SUMMARY_ITEMS

static final String[] SUMMARY_ITEMS

Method Detail

getQuiescentIOthreshold

long getQuiescentIOthreshold()

Returns:

the quiescentIOthreshold

setQuiescentIOthreshold

void setQuiescentIOthreshold(long quiescentIO)

Parameters:

quiescentIO - the quiescentIOthreshold to set

getIoRate

long getIoRate()

Returns:

the ioRate

setLogFile

void setLogFile(String toFile)
         throws IOException

Set the path for file into which IO events should be logged, or null to disable IO logging. Use care when enabling an I/O log because every I/O operation performed by Persistit results in a fixed-length record being added to the file. The resulting log file can become extremely large.

Parameters:

toFile -

Throws:

IOException

getLogFile

String getLogFile()

Returns:

Path for file into which IO events should be logged, or null if IO logging is disabled.

totalBytes

long totalBytes(String operation)

Parameters:

operation - An I/O operation name. Operation names are specified in OPERATIONS.

Returns:

Sum of size of all I/O operations of the specified operation type.

totalOperations

long totalOperations(String operation)

Parameters:

operation - An I/O operation name. Operation names are specified in OPERATIONS.

Returns:

Count of size of all I/O operations of the specified operation type.