Hi all,
When I came across SIB (Service Integration Bus) and it's working in Websphere Application Server. I think that it is very important to us to know about the some basic concept like Message Store so I just try to collect some information which is already there in IBM Knowledge Center.
A message store enables a messaging engine to preserve operating information and to retain those objects that messaging engines need for recovery in the event of a failure.
A messaging engine preserves both volatile and durable data in its message store. Volatile data is lost when a messaging engine stops, in either a controlled or an uncontrolled manner. Durable data is available after the server restarts. A messaging engine stores various types of data, including messages, transaction states, and communication channel states.
When started, a messaging engine obtains configuration information from the WCCM ( WebSphere Application Server Common Configuration Model) repository. A messaging engine retrieves all other data from its own file store or data store.
There are currently no facilities available for migrating from a data store to a file store.
• File stores
• Data stores
A file store is a type of message store that directly uses files in a file system through the operating system. The data storage in a file store is split into three levels:
1. Log file
2. Permanent store file
3. Temporary store file.
Log file :
This file contains information about currently active transactions and data that is not yet written to a store file. It is a circular log and its file size is static while a messaging engine is running, but can be changed if required. A restart of the messaging engine is required for the changes to take effect. The size of the log file limits the maximum size of a message that can be sent.
Permanent store file :
This file contains permanent data that is retained after the restart of the messaging engine, such as persistent messages, queue data, and information about the storage and transmission of persistent messages.
The permanent store file can be configured to have a maximum and minimum size, or to be unlimited in size. The file can grow from the minimum size (or as required in the unlimited case) but will never shrink (even if the maximum size is set lower than its current size). The file sizes can be changed in the administration console, but a restart of the messaging engine is required for the changes to take effect.
Similar to a file system, when data is deleted from the store, the data in the file is not deleted, only the directory information is updated. This means that if a message is consumed, the message data may still be present in the store file, but the directory information that includes this data in the store is updated to reflect the fact that it is deleted.
Temporary store file :
This file contains temporary data that is not retained after the restart of the messaging engine, such as nonpersistent messages that were spilled to the file store to release memory from the JVM heap. The temporary store file contents are truncated when the messaging engine starts.
The temporary store file can be configured to have a maximum and minimum size, or to be unlimited in size. The file can grow from the minimum size (or as required in the unlimited case) but will never shrink (even if the maximum size is set lower than its current size). The file sizes can be changed in the administration console, but a restart of the messaging engine is required for the changes to take effect.
Similar to a file system, when data is deleted from the store, the data in the file is not deleted, only the directory information is updated. This means that if a message is consumed, the message data may still be present in the store file, but the directory information that includes this data in the store is updated to reflect the fact that it is deleted.
You can configure where the file store files must be placed. By default, the file store uses a subdirectory in the following path:${USER_INSTALL_ROOT}/filestores/com.ibm.ws.sib/${ME_NAME}. The file store directory contains two other directories; the log directory that contains the log file and the store directory that contains both the PermanentStore and TemporaryStore files.
A data store consists of the set of tables that a messaging engine uses to store persistent data in a database. See Data store tables for a list of the tables that comprise a data store. All the tables in a data store are held in the same database schema. You can create multiple data stores in the same database, provided that you use a different schema name for each data store.
The one-to-one relationship between a messaging engine and a data store means that every messaging engine must have its own data store. A messaging engine uses an instance of a JDBC data source to interact with the database that contains the data store for that messaging engine. The relationship between a messaging engine and its data store. illustrates these relationships.
A messaging engine uses a JDBC data source to manage the interaction with a data store, which is held in a database
All the tables in the data store must be stored in the same schema. You can create more than one data store in a database, provided that you use a different schema name for each data store. Although every messaging engine uses the same table names, its relationship with the schema gives each messaging engine exclusive use of its own tables.
Data store topologies :
You have several options for the relative location of a data store and its messaging engine. The topology also defines the relationship of a data store with other data stores.
The following options affect your choice of data store topology:
1. The data store can either run on the same node as its messaging engine or on a remote node.
2. The data store can either have a dedicated database or it can share a database with other data stores.
The contain of this blog is referred from IBM Knowledge Center.
I Just try to make it easy for readers by gathering information under single blog. Hope this will help you.
When I came across SIB (Service Integration Bus) and it's working in Websphere Application Server. I think that it is very important to us to know about the some basic concept like Message Store so I just try to collect some information which is already there in IBM Knowledge Center.
Message stores
Message stores are important in the operation of messaging engines. To host queue-type destinations, a messaging engine includes a message store where, if necessary, it can hold messages until consuming applications are ready to receive them, or preserve messages in case the messaging engine fails. Each messaging engine has one and only one message store. This can either be a file store or a data store.A message store enables a messaging engine to preserve operating information and to retain those objects that messaging engines need for recovery in the event of a failure.
A messaging engine preserves both volatile and durable data in its message store. Volatile data is lost when a messaging engine stops, in either a controlled or an uncontrolled manner. Durable data is available after the server restarts. A messaging engine stores various types of data, including messages, transaction states, and communication channel states.
When started, a messaging engine obtains configuration information from the WCCM ( WebSphere Application Server Common Configuration Model) repository. A messaging engine retrieves all other data from its own file store or data store.
There are currently no facilities available for migrating from a data store to a file store.
• File stores
• Data stores
File stores
File stores use a file system to preserve operating information and to persist the objects that messaging engines need for recovery in the event of a failure.A file store is a type of message store that directly uses files in a file system through the operating system. The data storage in a file store is split into three levels:
1. Log file
2. Permanent store file
3. Temporary store file.
Log file :
This file contains information about currently active transactions and data that is not yet written to a store file. It is a circular log and its file size is static while a messaging engine is running, but can be changed if required. A restart of the messaging engine is required for the changes to take effect. The size of the log file limits the maximum size of a message that can be sent.
Permanent store file :
This file contains permanent data that is retained after the restart of the messaging engine, such as persistent messages, queue data, and information about the storage and transmission of persistent messages.
The permanent store file can be configured to have a maximum and minimum size, or to be unlimited in size. The file can grow from the minimum size (or as required in the unlimited case) but will never shrink (even if the maximum size is set lower than its current size). The file sizes can be changed in the administration console, but a restart of the messaging engine is required for the changes to take effect.
Similar to a file system, when data is deleted from the store, the data in the file is not deleted, only the directory information is updated. This means that if a message is consumed, the message data may still be present in the store file, but the directory information that includes this data in the store is updated to reflect the fact that it is deleted.
Temporary store file :
This file contains temporary data that is not retained after the restart of the messaging engine, such as nonpersistent messages that were spilled to the file store to release memory from the JVM heap. The temporary store file contents are truncated when the messaging engine starts.
The temporary store file can be configured to have a maximum and minimum size, or to be unlimited in size. The file can grow from the minimum size (or as required in the unlimited case) but will never shrink (even if the maximum size is set lower than its current size). The file sizes can be changed in the administration console, but a restart of the messaging engine is required for the changes to take effect.
Similar to a file system, when data is deleted from the store, the data in the file is not deleted, only the directory information is updated. This means that if a message is consumed, the message data may still be present in the store file, but the directory information that includes this data in the store is updated to reflect the fact that it is deleted.
You can configure where the file store files must be placed. By default, the file store uses a subdirectory in the following path:${USER_INSTALL_ROOT}/filestores/com.ibm.ws.sib/${ME_NAME}. The file store directory contains two other directories; the log directory that contains the log file and the store directory that contains both the PermanentStore and TemporaryStore files.
Data stores
A data store is a message store that uses a relational database. A messaging engine uses a data store to store operating information in the database, as well as to preserve essential objects that the messaging engine needs for recovery in the event of a failure.A data store consists of the set of tables that a messaging engine uses to store persistent data in a database. See Data store tables for a list of the tables that comprise a data store. All the tables in a data store are held in the same database schema. You can create multiple data stores in the same database, provided that you use a different schema name for each data store.
The one-to-one relationship between a messaging engine and a data store means that every messaging engine must have its own data store. A messaging engine uses an instance of a JDBC data source to interact with the database that contains the data store for that messaging engine. The relationship between a messaging engine and its data store. illustrates these relationships.
A messaging engine uses a JDBC data source to manage the interaction with a data store, which is held in a database
All the tables in the data store must be stored in the same schema. You can create more than one data store in a database, provided that you use a different schema name for each data store. Although every messaging engine uses the same table names, its relationship with the schema gives each messaging engine exclusive use of its own tables.
Data store topologies :
You have several options for the relative location of a data store and its messaging engine. The topology also defines the relationship of a data store with other data stores.
The following options affect your choice of data store topology:
1. The data store can either run on the same node as its messaging engine or on a remote node.
2. The data store can either have a dedicated database or it can share a database with other data stores.
The contain of this blog is referred from IBM Knowledge Center.
I Just try to make it easy for readers by gathering information under single blog. Hope this will help you.
"Effort only fully releases its reward after a person refuses to quit.”
Regards,
Akhilesh B. Humbe
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