LOGCOPY1.DS01 LOGCOPY2.DS01 LOGCOPY2.DS02

LOGCOPY2.DS03 LOGCOPY1.DS02 LOGCOPY1.DS03

Figure 39. Minimum Active Log Data Set Distribution

Preformat New Active Log Data Sets

The system administrator, when allocating new active log data sets, can preformat them using the DSNJLOGF utility described in Section 3 of DB2 for OS/390 Utility Guide and Reference, SC26-8967. This avoids the overhead of preformatting the log, which normally occurs at unpredictable times.

DSNTIPL

UPDATE DB2 - ACTIVE LOG DATA SET PARAMETERS

 

===>

 

 

 

 

 

 

Enter data below:

 

 

 

 

 

1

NUMBER OF LOGS

===>

3

Data sets per active log copy (2-31)

2

INPUT BUFFER

===>

60K

Size in bytes (28K-60K)

 

3

OUTPUT BUFFER

===>

4000K

Size in bytes (40K-400000K)

 

4

WRITE THRESHOLD

===>

20

Buffers filled before write (1-256)

5

ARCHIVE LOG FREQ

===>

24

Hours per archive run

 

6

UPDATE RATE

===>

3600

Updates, inserts, and deletes per hour

7

LOG APPLY STORAGE ===>

0M

Maximum ssnmDBM1 storage in MB for

 

 

 

 

 

fast log apply (0-100M)

 

F1=HELP

F2=SPLIT

F3=END

F4=RETURN

F5=RFIND

F6=RCHANGE

F7=UP

F8=DOWN

 

F9=SWAP

F10=LEFT

F11=RIGHT

F12=RETRIEVE

Figure 40. Installation Panel DSNTIPL

10.5 Log Reads

It is during a rollback, restart, and database recovery that the performance impact of log reads becomes evident. DB2 must read from the log and apply changes to the data on disk. Every process that requests a log read has an input buffer dedicated to that process. DB2 optimizes the log reads searching for log records in the following order:

1.Log output buffer

2.Active log data set

3.Archive log data set

If the log records are in the output buffer, DB2 reads the records directly from that buffer. If the log records are in the active or archive log, DB2 moves those log

DB2 I/O Operations 115

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IBM 5695-DF1, 5655-DB2 manual Log Reads, Preformat New Active Log Data Sets

5695-DF1, 5655-DB2 specifications

IBM 5655-DB2 and 5695-DF1 are significant components within the IBM software ecosystem, predominantly focusing on data management and integration solutions. These offerings cater primarily to enterprise environments that require robust database management systems and associated frameworks to maintain and manipulate data efficiently.

IBM 5655-DB2 is a well-known relational database management system (RDBMS) that excels in managing large volumes of structured data. Its architecture is designed to support high availability, scalability, and performance, crucial for businesses operating in today’s data-driven world. Some of its main features include advanced indexing capabilities, support for complex queries, and dynamic workload management. Additionally, it provides strong concurrency controls, which enable multiple users to access and manipulate data simultaneously without compromising data integrity.

One of the key characteristics of DB2 is its support for various data types, including JSON and XML, making it versatile for modern applications that generate data in diverse formats. It also features robust security mechanisms to protect sensitive data, aligning with compliance standards across industries. Integration with analytics tools further allows businesses to derive insights from their data, enhancing decision-making processes.

On the other hand, IBM 5695-DF1, also known as the InfoSphere DataStage, is a powerful data integration tool that facilitates the extraction, transformation, and loading (ETL) of data from various sources to target systems. It empowers organizations to streamline their data flows, ensuring that clean, consistent information is available for analysis and operational use. Key features of 5695-DF1 include a user-friendly graphical interface that enhances developer productivity and a rich set of connectors for numerous data sources, enabling seamless data integration.

DataStage also supports real-time data integration, allowing businesses to keep their data synchronized across multiple platforms. Its parallel processing capabilities dedicatedly optimize performance, enabling organizations to handle vast datasets efficiently. It incorporates data quality tools that help in validating and cleansing data before it is used for decision-making processes.

Both IBM 5655-DB2 and 5695-DF1 are part of a broader strategy to accommodate the evolving landscape of data management. Businesses leverage these technologies to enhance their data architectures, fostering agility and competitive advantage in their respective markets. Their integration capabilities, along with a focus on security and scalability, position them as vital assets in modern enterprise environments. Whether managing critical data within a database or ensuring seamless data flow across systems, these IBM offerings provide a comprehensive approach to handling complex data challenges.