Kbase P123340: Type II storage area growing rapidly due to corruption on the RM chain
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
5/14/2008 |
|
Status: Verified
FACT(s) (Environment):
All Supported Operating Systems
OpenEdge Category: Database
OpenEdge 10.x
All Supported Operating Systems
SYMPTOM(s):
Type II storage area growing abnormallly large.
Type II storage area not reusing space within the area.
Data within the Type II storage area is very small compared to the amount of disk space being utilized to hold the data.
MB (megabytes) worth of data being stored using multiple GB (gigabytes) of file system space.
dbanalys option to proutil showing 3916 error for area which is rapidly growing.
Empty block type found below highwater mark. Area "" : . (3916)
chanalys option to proutil showing 3910 and 6704 errors.
dbkey = (3910)
<name> Block <dbkey> with invalid chain type <number> on RM chain (6704)
CAUSE:
The storage area that is growing has two corrupted blocks on the RM chain. The output from chanalys is showing error 6704 associated with two blocks. One block with an unknown type (127 0x7f) and a second block whose chain type indicates it is on the Free chain, but they are both on the RM chain. Once this corruption is detected, the database engine will never use the remaining space on the RM chain. Rather we will continue to allocate space every time these blocks are detected on the RM chain.
FIX:
Empty blocks below the high water mark typically means that the storage engine was formatting blocks when the database crashed, or was forced down (-F) or the machine crashed. Crash recovery is suppose to take care of this but for some reason did not. Recommendation would be to rebuild the RM and Free chain using dbrpr. If dealing with an index, then the recommendations would be to rebuild the indexes in that area.
To address the corruption on the RM chain, the recommendation would be to dump the data from the area, truncate the area and then load the data back into the area.