pre configuration mode: single system vs standard

[Former Member]

Hi,

My business conrims that they do not need the system when we start the upgrade. so i assuem no downtime minimize is required since no one doing any thing in system.

i understand that down time minimized method can be considered when the business needs the system.

since they do not access the system during the upgrade, can i consider single system mode.

what is the impact of single system?

does the total run time changes?

which run time is much faster?

[Former Member · Accepted solution]

Hello,

Please see the description as below :

Characteristics of Upgrade Strategy Downtime-Minimized :

Parallel operation of production system and shadow system
Higher demand on system resources
Shorter downtime
Import of the substitution set into the shadow tables during production operation
Modification adjustment of the ABAP Dictionary objects during production operation
Activation and distribution during production operation
Used for the synchronized upgrade of a dual stack SAP system

Characteristics of Upgrade Strategy Resource-Minimized :

Operation of production and shadow system only possible independently of each other
Production operation stops before import of substitution set into shadow tables or, at the latest,
before shadow instance is started for first time.
Increased downtime
No ICNV
Cannot be used for the synchronized upgrade of a dual stack SAP system

To minimize downtime during the import of Support Packages or add-on installation queues, the standard import process has been modified. In particular, a new import procedure has been developed for ABAP sources and ABAP texts, which imports changes made to ABAP program objects (for example, report sources, function groups, ABAP OO classes, function modules, or methods) to the database in an inactive state. As a result, the ABAP runtime environment does not yet take these new versions into account. This import can therefore take place while you productively use the system, which reduces the downtime that is required.

              Unlike in other procedures, the data that is inactive when it is imported is saved in the same tables as the active data. The advantage of this procedure is that it is not necessary to set up a system of shadow tables (as is the case for the release upgrade, for example). The procedure is therefore less complex. However, the disadvantage of this procedure is that the imports change the system while it is still productively used. As a result, the point of no return and the beginning of the downtime do not occur at the same time.

Award points if useful.

Thanks,

Ravi

[Former Member · Accepted solution]

Hi Ravi,

which one decreases the run time?

Thanks,

Maheh Guta

[Former Member · Accepted solution]

Hi Mahesh,

Downtime minimized decreases the runtime as it uses higher resources and uses parallel processing.

Thanks,

Ravi

[former_member189725 · Accepted solution]

The runtime is the upgrade runtime which is minimized using the resource-minimized mode where only one instance is up (either the actual instance or the shadow instance) at any particular time.  This ensures that the shadow instance can use all the available resources on the system. This increases the downtime of the system which means the system cannot be used productively by the users.

On the other hand , downtime minimized mode increases the over all runtime of the upgrade , but the downtime of the system decreases and the users can productively use the system for a longer duration compared to the previous case. In this case both the instances (main and shadow) run in parallel and the hardware resources in the system are shared by both the instances.

Regards

Ratnajit

[Former Member · Accepted solution]

Hi Ratnajit,

did you get a chance to check the both pre configuration modes?  what was the total runtime for both. was their any difference?

Thanks,

Mahesh Gutta

[former_member189725 · Accepted solution]

I have preferably used downtime-minimized as I wanted a minimal downtime for the users. But it would definitely have difference in runtimes for the 2 modes. How much difference depends on the hardware in question . Assume somewhere between  5 to10 hrs.

I would suggest you use one pre-configuration mode for all systems in a landscape.

Regards

Ratnajit