9.4.4  Problem determination tools

Tuning and troubleshooting a database can be a complex process. DB2 UDB 

comes with a great number of tools, functions, and applications that make this 

task much simpler.

Monitoring tools

DB2 UDB monitoring utilities can collect information on many different system 

activities like usage of buffer pools, locks held by applications, sorts performed 

by system, activities on tables, connections, transactions statistics or statements 

run on the system. There are two main methods of monitoring:

Snapshot monitoring 

Event monitoring

Snapshot monitoring 

Snapshot monitoring describes the state of database activity at the particular 

point in time the snapshot is taken. Snapshot monitoring is useful in determining 

the current state of the database and its applications. Because snapshots 

provide the point in time data, they are usually executed in scripts on regular 

intervals.

Snapshots can be taken from the command line, using custom API programs or 

through SQL using 

table functions

. Example 9 9 shows the extract from a sample 

snapshot invoked from the command line. 

Example 9 9   Example snapshot

db2 get snapshot for database on db2_emp

              Database Snapshot

Database name                              = DB2_EMP

Database path                              = 

/db2/home/db2inst1/db2inst1/NODE0000/SQL00001/

Input database alias                       = DB2_EMP

Database status                            = Active

[...]

High water mark for connections            = 3

Application connects                       = 7

Secondary connects total                   = 0

Applications connected currently           = 1

Appls. executing in db manager currently   = 0

Agents associated with applications        = 1

Maximum agents associated with applications= 1

Maximum coordinating agents                = 1

[...]

 Chapter 9. Testing and tuning 

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