Estimating the logical-log size when logging simple large objects

To obtain better overall performance for applications that perform frequent updates of TEXT or BYTE data in blobspaces, reduce the size of the logical log.

Blobpages cannot be reused until the logical log to which they are allocated is backed up. When TEXT or BYTE data activity is high, the performance impact of more frequent checkpoints is balanced by the higher availability of free blobpages.

When you use volatile blobpages in blobspaces, smaller logs can improve access to simple large objects that must be reused. Simple large objects cannot be reused until the log in which they are allocated is flushed to disk. In this case, you can justify the cost in performance because those smaller log files are backed up more frequently.


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