Specifying lightweight I/O for smart large objects

To specify the use of lightweight I/O when creating the sbspace, use the BUFFERING tag of the -Df option in the onspaces -c -S command.

The default value for BUFFERING is ON, which means to use the buffer pool. The buffering mode that you specify (or the default, if you do not specify) in the onspaces command is the default buffering mode for all smart large objects stored within the sbspace.
Important: In general, if read and write operations to the smart large objects are less than 8080 bytes, do not specify a buffering mode when you create the sbspace. If you are reading or writing short blocks of data, such as 2 kilobytes or 4 kilobytes, leave the default of “buffering=ON” to obtain better performance.
Programmers can override the default buffering mode when they create, open, or alter a smart-large-object instance with DataBlade API and the Informix® ESQL/C functions. The DataBlade API and the Informix ESQL/C application programming interface provide the LO_NOBUFFER flag to allow lightweight I/O for smart large objects.
Important: Use the LO_NOBUFFER flag only when you read or write smart large objects in operations greater than 8080 bytes and you seldom access them. That is, if you have infrequent read or write function calls that read large amounts of data in a single function invocation, lightweight I/O can improve I/O performance.

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