Does CA Disk exploit zIIP ?

Document ID : KB000013071
Last Modified Date : 14/02/2018
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Does CA Disk exploit zIIP ? 


Currently CA-DISK does not exploit zIIP processors. 

CA Disk is not a good candidate for using zIIP since using SRB mode is required. 

SRB mode means no SVC's can be issued and no I/O which is what CA Disk mainly does. 

Our data compression might be the only place we could use zIIP. 

Please see and vote for the “Enhancement Idea“ to make at least the CPU intensive data compression process of CA Disk eligible for zIIP, see link - 



Additional Information:

If you use data compression via sysparm DCDATACP in your BACKUP/ARCIVE jobs, you need to make sure PTF RO86193 is installed. It corrects a performance problem when using DCDATACP = Y and the default of DCCOMPTC = 0 on a z/Architecture processor. 


If you are using a DATACOM Files DB, then Datacom/AD can use zIIP processing using startup options SMPTASK and ZIIP_USER_LIMIT. You must run tasks in SRB mode to use zIIP processing. Specify SRB mode in the SMPTASK MUF startup option (see SMPTASK). The ZIIP_USER_LIMIT MUF startup option can be useful as a tuning option but is not required to do zIIP processing. 

There is a MUF EOJ Report for zIIP which should show if zIIP is enabled correctly, see section "ENCLAVE SRB USE SUMMARY INFORMATION" of the MUF EOJ Report. 

For details, see Chapter 4: zIIP Processors in the CA DATACOM/DB Database and System Administration Guide. 


Using a Datacom Files DB, processes which make a lot of use of the Datacom FDB, like IXMAINT or LISTD, should see a reduction, but ARCHIVE and BACKUP would not much.