Transcript Data Libraries per Location?

Optimizing Batch Job Performance
Optimizing Batch Job Performance
• Resources Consumed by Program
• I/O by Database File Name
• Delays Caused by Object Locks
• Heaviest Active Job Function Names
• Record Lock Contention
• Time Spent on Job Status
• CPU by Line of Source Code
• Duration of ILE Modules
• Elapse Time by ILE Procedure Name
System Navigator
Identify Job Level
Bottleneck First!!
Workload Navigator
Is the job CPU,
Memory or
I/O bound?
Resources Consumed by Program
Resources Consumed by Program
• “Job” versus “Job Stream”
• Application or Operating System
• CPU, I/O, Memory, Elapse Time
• Date Routines, Tax Calculation Routine
• Imbedded SQL, High Initiation/Termination
• Stand-alone or Hundreds of Calls
• ILE w/ Many Modules versus OPM Program
Operating System Level
Operating System Level
Application Level
Application Level
I/O by Database File Name
I/O by Database File Name
• Compare Percent Reads to Writes/Updates
• Number of I/Os versus Records in File
• Small I/O Counts, Files Opening/Closing
• High Sequential Reads, Low Random Reads
• Time to Purge or Move Some Data?
• “Open Orders” File w/ 7 Years of Closed
• Proper Logical Views for Quick Access
I/O Example
Delays Caused by Object Locks
Delays Caused by Object Locks
• Work Files that Should be in QTEMP
• Separate Data Libraries per Location?
• Hundreds of Jobs Daytime, One Job at Night
• Rare Situations Require Exclusive Locks!
• CPYF CRTFILE(*YES) vs. CRTDUPOBJ
• Fix the Job, Don’t Live w/ Consequences
• Older Code more Prone to Locking Issues
Lock Wait Job Status
Locks by Object Name
Heaviest Active Job Function Names
Heaviest Active Job Function Names
• Job Going In and Out of Short DLYJOBs
• Operating System Rebuilding Access Paths
• Job Copying Data with Selection Criteria
Job Function Example
Record Lock Contention
Record Lock Contention
• Don’t Single Thread, Fear of Record Locks
• Not a Bigger Issue at Night versus Daytime
• Automatic Notification and Retry
• Monitor Time Spent in Lock Wait Status
• Release Records in Code if Causing Delays
Record Lock Example
Time Spent on Job Status
Time Spent on Job Status
• Never Ending Job, Always in RUN Status?
• Nightly Job, not Always in RUN Status?
• DLYJOB used as Bad Timing Technique
• Object Locks for Long Periods of Time
• Short Object Locks, Thousands of Times
• Data Queue Wait that Never Waits!
• Job Waits on Message for Hours Nightly
Job Status Example
CPU by Line of Source Code
CPU by Line of Source Code
• Is There One Bad Line of Code?
• SETON LR at end of Date Routine
• CHAIN to CustMast for Every Line Item
• Open/Close 50 Files for Each Line Item
• OPNQRYFs are 73% of CPU and Elapse
• CALL to Tax Routine, 85% of Elapse
• Format Date Routine, 93% of Duration
Source Code Example
Duration of ILE Modules
Duration of ILE Modules
• Complex ILE Bound Program
• Identify Specific Module Causing Delays
• Date Routines, Tax Calculation Routine
• Older Routines, Called for Every Line Item
• Outside Loop, Now that Impact is Known
ILE Modules Example
Elapse Time by ILE Procedure Name
Elapse Time by ILE Procedure Name
• Identify High Use Subroutines
• Optimize Those Routines
• Minimize Calls to Intensive Routines
• Pinpoint Section of Code Needing Rework
ILE Procedure Name Example
Q&A
Questions & Answers
To receive MB Software’s FREE performance evaluation:
1. Register at http://www.mb-software.com
2. Download and install software on AS/400 or iSeries
3. Call (800) 713-5034 to schedule your free performance review session
What To Expect:
After allowing performance data to accumulate for one full business day, you will log into a secure
area of MB Software’s web site. We will then have a conference call to discuss our findings and
how you can gain performance improvements with your existing applications. It’s that easy!