Kbase 20396: -Mf and Its Impact on the Database
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
3/17/2003 |
|
Status: Verified
GOAL:
The -Mf value and how it works in a crash recovery
FIX:
The -Mf value controls the number of seconds a partially filled before-image (BI) buffer can sit in memory before being written out to disk. Set -Mf to its default value of 3, although there is no risk of data corruption if you set it to a higher value.
The data is not corrupted by a crash recovery. BI buffers can still be written to disk before the timeout expires (for example, when the buffers are filled). However, there is a small chance that in the event of a crash, a committed transaction whose transaction end note is still in memory will be rolled back during the crash recovery. This can happen because the commit note might be lost in a crash.