weblogic.management.configuration
Interface JMSFileStoreMBean

public interface JMSFileStoreMBean

extends JMSStoreMBean

This class represents a JMS file-based persistent store.

Field Summary

static long

CACHING_STUB_SVUID

Fields inherited from class weblogic.management.configuration.JMSStoreMBean

CACHING_STUB_SVUID

Fields inherited from class weblogic.management.configuration.ConfigurationMBean

CACHING_STUB_SVUID

Method Summary

java.lang.String	getDirectory() Defines the directory where the file-based persistent store exists.
java.lang.String	getSynchronousWritePolicy() The WebLogic JMS file store provides three synchronous write policies: Disabled, Cache-Flush, and Direct-Write.
void	setDirectory(java.lang.String directory) Defines the directory where the file-based persistent store exists.
void	setSynchronousWritePolicy(java.lang.String policy)

Methods inherited from interface weblogic.management.configuration.JMSStoreMBean

getJMSServer

Methods inherited from interface weblogic.management.configuration.ConfigurationMBean

addLinkMbeanAttribute, getNotes, isPersistenceEnabled, setNotes

Methods inherited from interface weblogic.management.WebLogicMBean

getMBeanInfo, getName, getObjectName, getParent, getType, isCachingDisabled, isRegistered, setName, setParent

Methods inherited from interface javax.management.DynamicMBean

getAttribute, getAttributes, invoke, setAttribute, setAttributes

Methods inherited from interface javax.management.MBeanRegistration

postDeregister, postRegister, preDeregister, preRegister

Methods inherited from interface javax.management.NotificationBroadcaster

addNotificationListener, getNotificationInfo, removeNotificationListener

Field Detail

CACHING_STUB_SVUID

public static final long CACHING_STUB_SVUID

Method Detail

getDirectory

public java.lang.String getDirectory()

Defines the directory where the file-based persistent store exists.

This attribute is not dynamically configurable.

setDirectory

public void setDirectory(java.lang.String directory)
                  throws javax.management.InvalidAttributeValueException

Defines the directory where the file-based persistent store exists.

This attribute is not dynamically configurable.

Legal Value: value != void && value.trim().length() != 0

Legal NULL: false

getSynchronousWritePolicy

public java.lang.String getSynchronousWritePolicy()

The WebLogic JMS file store provides three synchronous write policies: Disabled, Cache-Flush, and Direct-Write. These policies configure how the file store writes data to disk, and affect performance, scalability, and reliability.

Disabled -- File store writes are allowed to use both the operating system's cache as well as the file system's on-disk cache. This policy is the fastest, but the least reliable. It can be more than 100 times faster than the other policies, but power outages or operating system failures can cause lost and/or duplicate messages.

Cache-Flush -- The default policy. Transactions cannot complete until all of their writes have been flushed down to disk. This policy is reliable and scales well as the number of simultaneous users increases.

Direct-Write -- File store writes are written directly to disk. This policy is supported on Solaris, HP, and Windows. If this policy is set on an unsupported platform, the file store automatically uses the Cache-Flush policy instead. The Direct-Write policy's reliability and performance depend on operating system and hardware support of on-disk caches, as follows:

• With on-disk caching enabled, the Direct-Write policy can be 2-5 times faster than the Cache-Flush policy, except in highly scalable cases where it may be slightly slower.

• With on-disk caching disabled, the Direct-Write policy is faster than the Cache-Flush policy in one-to-many cases, but is much slower otherwise.

• The Direct-Write policy scales well with on-disk caching enabled, but does not scale with it disabled. (Solaris does not allow enabling the on-disk cache for direct writes).

Warning! Unlike Solaris and HP, use of the Direct-Write policy on Windows may leave transaction data in the on-disk cache without writing it to disk immediately. This is not transactionally safe (i.e., not reliable), since a power failure can cause loss of on-disk cache data-- possibly resulting in lost and/or duplicate messages. For reliable writes using Direct-Write on Windows, either disable all write caching for the disk (enabled by default), or use a disk with a battery backed cache.

To disable the on-disk cache for a hard drive on Windows:
Start -> Settings -> Control Panel -> System -> Hardware tab -> Device Manager button -> Disk Drives -> double-click drive name -> Disk Properties tab -> deselect "Write Cache Enabled" check box. Some file systems do not allow this value to be changed (for example, a RAID system that has a reliable cache).

Note: If the JMS file store is used exclusively for paging non-persistent messages to disk, the synchronous write policy is ignored.

A dynamic MBean attribute

Default Value: weblogic.management.configuration.JMSConstants.SYNCWRITE_CACHEFLUSH

Legal Values: weblogic.management.configuration.JMSConstants.SYNCWRITE_DISABLED,weblogic.management.configuration.JMSConstants.SYNCWRITE_CACHEFLUSH,weblogic.management.configuration.JMSConstants.SYNCWRITE_DIRECTWRITE

setSynchronousWritePolicy

public void setSynchronousWritePolicy(java.lang.String policy)
                               throws javax.management.InvalidAttributeValueException,
                                      DistributedManagementException