com.persistit.mxbeans

Interface TransactionIndexMXBean

@MXBean
public interface TransactionIndexMXBean

Management interface to the TransactionIndex. Statistics provided here are generally only useful for diagnostic purposes.

Field Summary

Fields

Modifier and Type	Field and Description
static String	MXBEAN_NAME

Method Summary

Modifier and Type	Method and Description
void	cleanup() Remove all obsolete long-running and aborted TransactionStatus instances.
int	getAbortedCount()
long	getActiveTransactionCeiling() Timestamp recorded at the start of the last invocation of updateActiveTransactionCache.
long	getActiveTransactionCount() Count of active transactions measured when updateActiveTransactionCache was last called.
long	getActiveTransactionFloor() Timestamp known to be less than or equal to the start timestamp of any currently executing transaction.
int	getCurrentCount()
int	getDroppedCount()
int	getFreeCount()
int	getLongRunningCount()
void	updateActiveTransactionCache() Refresh the ActiveTransactionCache.

Field Detail

MXBEAN_NAME

static final String MXBEAN_NAME

See Also:

Constant Field Values

Method Detail

getActiveTransactionFloor

long getActiveTransactionFloor()

Timestamp known to be less than or equal to the start timestamp of any currently executing transaction. This value is computed by updateActiveTransactionCache and is therefore less the timestamp of any currently executing transaction at the instant that method was called. It is guaranteed that no running transaction has a lower start timestamp.

Returns:

Lower bound on start timestamps of currently active transactions.

getActiveTransactionCeiling

long getActiveTransactionCeiling()

Timestamp recorded at the start of the last invocation of updateActiveTransactionCache. Any transaction newer than this ceiling is currently considered active even if it has already committed or aborted.

Returns:

Upper bound on timestamps for which hasConcurrentTransaction returns accurate information.

getActiveTransactionCount

long getActiveTransactionCount()

Count of active transactions measured when updateActiveTransactionCache was last called. The count may have changed to due new transactions starting or existing transactions committing since that invocation, and therefore the value returned by this method is an estimate.

Returns:

the count

updateActiveTransactionCache

void updateActiveTransactionCache()

Refresh the ActiveTransactionCache. This method walks the hashTable to update the non-current ActiveTransactionCache instance and then makes it current. This method will acquires an exclusive lock on the ActiveTransactionCache.

cleanup

void cleanup()

Remove all obsolete long-running and aborted TransactionStatus instances. This is useful to generate a canonical state for unit tests. Cleanup logic is normally invoke automatically within a running system..

getCurrentCount

int getCurrentCount()

Returns:

The approximate count of TransactionStatus instances on the current list.

getLongRunningCount

int getLongRunningCount()

Returns:

The approximate count of TransactionStatus instances on the long-running list.

getAbortedCount

int getAbortedCount()

Returns:

The approximate count of TransactionStatus instances on the aborted list.

getFreeCount

int getFreeCount()

Returns:

The approximate count of TransactionStatus instances on the free list.

getDroppedCount

int getDroppedCount()

Returns:

The approximate count of TransactionStatus instances that have been dropped.