db2pd -dbptnmem
The db2pd -dbptnmem command shows how much memory the DB2 server is currently consuming and, at a high level, which areas of the server are using that memory.
Here is an example of the output from db2pd -dbptnmem on an AIX machine:
Database Partition Memory Controller Statistics Controller Automatic: Y Memory Limit: 122931408 KB Current usage: 651008 KB HWM usage: 651008 KB Cached memory: 231296 KB
Here are the descriptions of these data fields and columns:
- Controller Automatic: Y if the instance_memory configuration parameter is set to AUTOMATIC. This means that database manager automatically determines the upper boundary on memory consumption.
- Memory Limit: The DB2 server's upper bound of memory that can be consumed. It is the value of the instance_memory configuration parameter.
- Current usage: The amount of memory the server is currently consuming.
- HWM usage: The high water mark (HWM) or peak memory usage that has been consumed since the activation of the database partition (when the db2start command was run).
- Cached memory: How much of the current usage is not currently being used, but is cached for performance reasons for future memory requests.
The continuation of the sample output from the db2pd -dbptnmem on AIX is shown below.
Individual Memory Consumers: Name Mem Used (KB) HWM Used (KB) Cached (KB) =========================================================== APPL-DBONE 160000 160000 159616 DBMS-name 38528 38528 3776 FMP_RESOURCES 22528 22528 0 PRIVATE 13120 13120 740 FCM_RESOURCES 10048 10048 0 LCL-p606416 128 128 0 DB-DBONE 406656 406656 67200
All registered "consumers" of memory within the DB2 server are listed with the amount of the total memory they are consuming. The column descriptions are:
- Name: A brief, distinguishing name of a "consumer" of memory. Examples include:
-
APPL-
for application memory consumed for database - DBMS-xxx for global database manager memory requirements
- FMP_RESOURCES for memory required to communicate with db2fmps
- PRIVATE for miscellaneous private memory requirements
- FCM_RESOURCES for Fast Communication Manager resources
-
LCL-
for memory segment used to communicate with local applications -
DB-
for database memory consumed for database - Mem Used (KB): How much memory is currently allotted to that consumer.
- HWM Used (KB): High-Water Mark, or Peak, memory that the consumer has used.
- Cached (KB): Of the Mem Used (KB), the amount of memory that is not currently being used but is immediately available for future memory allocations.