Recommendation to increase the MESSAGEMAX and COMMANDMAX Parameters

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Article ID: 205733

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Updated On:

Products

CA OPS/MVS Event Management & Automation

Issue/Introduction

Last week OPSMVS got crashed due to maximum command reached on product. What are the recommended values for the parameters MESSAGEMAX and COMMANDMAX. 

Possible error messages due to one of these parameter values being exceeded:

OPS3146S EMERGENCY PRODUCT SHUTDOWN STARTED - MAXIMUM COMMAND RATE EXCEEDED   
OPS3146S EMERGENCY PRODUCT SHUTDOWN STARTED - MAXIMUM MESSAGE RATE EXCEEDED  

 

 

 

 

 

 

Environment

Release : 13.5

Component : OPS/MVS

Resolution

The values below are generally used for these parameters:

COMMANDMAX 4000
COMMANDRATE 100

MESSAGEMAX 10000
MESSAGERATE 1000

As a general rule, check he value of the parameter COMMANDHIGH and MESSAGEHIGH on the OPSVIEW panel 4.1.1. If you see they are reaching their respective maximum values then you need to increase them.

Additional Information

Besides COMMANDMAX and COMMANDRATE there are some other parameter that may help you tuning this scenario. 
OPS keeps a counter of commands issued in the COMMANDCURRENT display-only parameter. When COMMANDCURRENT reaches the value of COMMANDMAX the emergency shutdown occurs. 
COMMANDRATE is value that is decremented from COMMANDCURRENT at each second. This mechanism makes COMMANDCURRENT kind of a buffer with size equal to the value of the parameter COMMANDMAX to allow OPS to issue commands at a higher rate during short periods of time. Only when the number of commands issued remains high for a longer period all the "buffer" becomes full because the rate at each the commands are removed from there (COMMANDRATE) is not enough to avoid that COMMANDCURRENT reaches COMMANDMAX.

There is another parameter that can help you determine the values of COMMANDMAX and COMMANDRATE that is COMMANDHIGH. If you monitor the value of COMMANDHIGH you will know how close your OPS region is/was from reaching COMMANDMAX since it was last started. If you see COMMANDHIGH approaching COMMANDMAX then you should first investigate if this was due to normal processing and then adjust the values of COMMANDMAX and COMMANDRATE accordingly.

You can change COMMANDHIGH dynamically in the OPSVIEW panel 4.1.1 in case you want to reset its value to start a new period of monitoring.