Broker 10.5 | webMethods Broker Documentation | Administering webMethods Broker | Managing Document Types | What Are Documents and Document Types? | Document Type Properties | Document Type Storage Types
Document Type Storage Types
The document storage type setting determines how instances of that document are persisted. Documents published to Broker can be stored as volatile documents or guaranteed documents.
*Volatile documents are stored in local memory only. These documents are lost if the Broker host experiences a service interruption or the Broker Server is restarted.
To reduce memory usage, volatile documents that have expired can be proactively deleted at regular intervals, based on the size of the queue, from the client queues and forward queues before the client tries to retrieve them. For more information, see Proactively Deleting Documents from a Client Queue.
Volatile storage provides higher performance than guaranteed storage; however, there is a greater risk of losing documents if a hardware, software, or network failure occurs. All documents of a volatile document type and documents in a volatile client queue are lost when the Broker is shut down or when the computer restarts. This storage type is suited for documents that have a short life span or are not critical.
*Guaranteed documents are persisted to disk so that they can be recovered in the event of a power failure or a server restart. This is the default storage type for document types.
Guaranteed storage provides lower performance than volatile storage, but very little risk of losing events if a hardware, software, or network failure occurs. This type of storage is the safest, and is suited for documents that you do not want to lose.
Guaranteed storage has a fixed, preallocated size that can only be changed while the Broker is stopped. This size is a function of the document flow and of the size of the documents. The default guaranteed storage size is 32MB per document and 512MB total for all guaranteed, queued documents. You can increase the storage size by adding new storage files (see Adding a Storage File).