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Sap Parameter Checks

By: saji
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SAP parameters

 

Parameter Guideline Values SAP Transaction Unix Command Comments
CPU Management        
Utilization Utilization < 65% idle > 20% OS06  vmstast -S 5 9 High CPU utilization indicates that the database machine needs more and faster cpus or a upgrade and for the application server we might need to distribute loads across the other application server
Processor Activity Utilization < 65% idle > 20% OS06 sar -M, top, vmstat -S 5 9  System/Memory/Process Monitor - Use this to determine what processes are consuming the most memory and cpu
 Load Average >3 processes in queue = problem OS06 or ST06 --- OS06 shows an average of more than 3 processes waiting in front of the CPU, then its an alarm to increase the CPUs.
 Process Information

 High values in column b is an indicator of a I/O bound system.

 High values in column r is an indication that the CPU is a problem.

---- vmstat -S 5 9  The three columns under procs show the number of processes in the run queue (r), the number of blocked processes (b), and the number of swapped runnable or short sleeper processes (w). High values of r is an indication that CPU performance is a problem.
Memory Management        
% Free  How much Physical memory is actually available to use. OS06 --- Check from Goto Current data Previous hours Memory. In a small hardware configuration, CPU bottlenecks are apparent when physical memory free is less than 10 MB.
Page In /Page Out

Minimize page activity.

Swap Memory

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Data Buffer Hit Ratio

SAP recommends that you maintain a data buffer quality of at least 97% on a production R/3 System.

Redo Log Buffer Allocation Fault Rate

  Fault rate is = ratio of redo allocation retries to the total redo entries.

This fault rate at 0% is ideal.

Data Dictionary cache Hit Ratio

> 90%

  %.

SQL Area getratio / pinratio

  % and pinratio %.

Recursive Call Ratio

Ratio of recursive calls to user calls < 10%

If the number of Recursive calls is greater than the number of User calls, then you should start a detailed examination. Recursive Calls are a result of low DD cache.

Database Management

       

Full Table Scans

Un-indexed Tables

All tables should have at least a primary index

 

Disk Management

       

High Disk Activity

 

Long Disk Queues

queue < 2-4

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DBWR Processes

  to the # of controllers

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Balanced Disk I/O

Would like to even distribution of load -

 

 

 

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