Cache Activity (SAP DB)
Activity for the following R/3 cache types is displayed in the
Database Monitor :Cache Type |
Cache Function |
Data |
Cache for data pages already accessed |
Converter |
Cache for administering assignment of logical to physical data pages When data pages not in the data cache are accessed, the system first searches for their physical position in the data dev spaces located in the converter cache. |
Rollbacks |
Cache for the rollbacks |
Catalog |
Cache containing the table descriptions needed to parse SQL statements. |
Cache Hits
The cache hit rate is:
The number of times the requested information was found in the cache divided by the total number of requested accesses.
In other words, the number of hits divided by the total number of accesses.
In a balanced system, the hit rata for the data and converter cache should be above 98%, for the catalog cache above 90%.
In general, the lower the hit rate, the less efficient the database.
See also: