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Title
More information on DB2 Memory Buffer Pool data -
Description
In the DB2 details screen under the 'Memory' -> Buffer pool -> under the activity tab, there are charts which displays read time and write time.
What is this data?
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Cause
DB2 metrics from the bufferpool logical group snapshot information are described in the following locations from the IBM DB2 documentation:
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Resolution
The charts in the Buffer Pools area correspond to the following metrics, in the form of a rate (divided by seconds)
Read Time = POOL_READ_TIME
Write Time = POOL_WRITE_TIME
Total Logical Reads Rate = TOTAL_LOGICAL_READS
Total Physical Reads Rate = TOTAL_PHYSICAL_READS
Data Logical Read Rate = DATA_LOGICAL_READS
Data Physical Reads Rate = DATA_PHYSICAL_READS
Index Logical Reads Rate = INDEX_LOGICAL_READS
Index Physical Reads Rate = INDEX_PHYSICAL_READSpool_read_time - Total buffer pool physical read time monitor element, this indicates the total amount of time spent reading in data and index pages from the table space containers (physical) for all types of table spaces. This value is given in milliseconds.
pool_write_time - Total buffer pool physical write time monitor element, this provides the total amount of time spent physically writing data or index pages from the buffer pool to disk. Elapsed time is given in milliseconds.
POOL_DATA_L_READS - pool_data_l_reads - Buffer pool data logical reads
POOL_DATA_P_READS - pool_data_p_reads - Buffer pool data physical reads
POOL_DATA_WRITES - pool_data_writes - Buffer pool data writes
POOL_INDEX_L_READS - pool_index_l_reads - Buffer pool index logical reads
POOL_INDEX_P_READS - pool_index_p_reads - Buffer pool index physical reads
POOL_INDEX_WRITES - pool_index_writes - Buffer pool index writes
POOL_READ_TIME - pool_read_time - Total buffer pool physical read time
POOL_WRITE_TIME - pool_write_time - Total buffer pool physical write timeThese values are total physical and logical reads for all bufferpools for all active databases for the currently connected database partition (respectively).
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Additional Information
I was able to find all of these metrics in the topology here: Management Server > All Data > DB2_Data_Model > DB2 Data Model > Instances > {instance name} > Databases > {db name} > Table Spaces Buffer pool > {tablespace name}