Physical recovery complete: number pages examined, number pages restored.

Cause

This message displays during fast recovery. The number of pages examined indicates the number of page images that exist in the physical log. The number of pages restored indicates the actual number of pages that are restored from the physical log. The number of pages restored is always less than or equal to the number examined.

The database server might physically log a page image multiple times between checkpoints. Physical recovery restores only the first logged page image.

If a page stays in the memory buffer pool, the database server physically logs it once per checkpoint, and stores one page image in the physical log. If the buffer pool is too small, a page that is being updated many times might get forced out of the buffer pool to disk and then brought back into memory for the next update. Each time the page is brought into memory, it is physically logged again, resulting in duplicate page images in the physical log.

Action

If the number of pages examined is much larger than the number of pages restored, increase the size of the buffer pool to reduce the number of duplicate before-images. For more information, see the HCL Informix® Performance Guide.


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