Through DB2 we can get the average time in ms disk access is having DB2. These times are crucial for the detection of a IO problem with DB2 instance.
Usually we take into consideration that a value close to 2-3ms is good, more than 10ms can indicate problems.
Avg ms/write:
select trunc(decimal(sum(pool_write_time))/decimal( (sum(pool_data_writes)+sum(pool_index_writes))),3) from sysibmadm.snaptbsp
Avg ms/read:
select trunc(decimal(sum(pool_read_time))/decimal( (sum(pool_data_p_reads)+sum(pool_index_p_reads))),3) from sysibmadm.snaptbsp
To obtain correct values, you must have activated monitor switches, you can view the status with the sentence “get monitor switches”.