Hi Bruno,

Can you please check in the shadow instance if the job RSGEN_GENER8_SHADOW is really running or just in the hang status. Also check the job log for more information.

Also check the below information from the SUM guide

Checking SUM Guide - 3.10.5

If you selected the Advanced preconfiguration mode, you need to choose

an execution strategy for the ABAP load generation (transaction SGEN).

You can select one of the following SGEN execution modes:

Release upgrade only: Do not start ABAP load generation during the

upgrade Enhancement package installation and SPS update: Do not start

ABAP load generation during the update

If you plan to apply a high number of relevant changes to your system

after the update in the form of a transport or a Support Package, we

recommend that you generate the ABAP loads manually after the update.

For more information about starting the load generation manually, see

Generating Loads [page 157].

Generate ABAP loads on shadow system during uptime

With this option, the Software Update Manager uses the maximum number of

processes entered below to generate the loads in the shadow system

during the uptime.

Generate ABAP loads on shadow system during uptime and start

asynchronously in post downtime.

With this option, the Software Update Manager uses the maximum number of

processes entered below to generate the ABAP loads in the shadow system

during the uptime. The transaction SGEN automatically starts again after

the downtime during the Postprocessing roadmap step to regenerate the

ABAP loads that were invalidated during the downtime.

https://websmp207.sap-ag.de/~sapidb/011000358700000783532011E

If you update a production system, you have to consider the impact on

production operation. If you choose the standard or advanced

preconfiguration mode, the shadow system is operated during uptime. This

means that the source release system and the shadow system compete for

the system resources. If the resource usage is of concern for the

system, it makes sense to choose the preconfiguration mode standard

since this mode uses only a limited amount of system resources.q[Å._B

If you update a production system with a high demand for minimal

downtime, the impact of the running shadow system on the source release

system might not be important. In this case, it could make sense to

choose advanced to shorten the overall runtime as much as possible.

Thank You.

Regards,

Deepika

phase RUN_RSGEN during EHP6 implementation takes a lot of time