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Tivoli Storage Manager Using the Application Program Interface

dsmBeginTxn

The dsmBeginTxn function call begins one or more TSM transactions that begin a complete action; either all the actions succeed or none succeed. An action can be either a single call or a series of calls. For example, a dsmSendObj call that is followed by a number of dsmSendData calls can be considered a single action. Similarly, a dsmSendObj call with a dataBlkPtr that indicates a data area containing the object to back up is also considered a single action.

Try to group more than one object together in a single transaction for data transfer operations. Grouping objects results in significant performance improvements in the TSM system. From both a client and a server perspective, a certain amount of overhead is incurred by starting and ending each transaction.

There are limits to what you can perform within a single transaction. These restrictions include:

With the API, either the application client can monitor and control these restrictions, or the API can monitor these restrictions. If the API is monitoring restrictions, appropriate return codes from the API calls inform the application client when one or more restrictions are reached.

Always match a dsmBeginTxn call with a dsmEndTxn call to optimize the set of actions within a pair of dsmBeginTxn and dsmEndTxn calls.

Syntax

dsInt16_t dsmBeginTxn  (dsUint32_t dsmHandle);

Parameters

dsUint32_t dsmHandle (I)
The handle that associates this call with a previous dsmInitEx call.

Return Codes

There are no return codes that are specific to this call.


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