phase RUN_RSGEN during EHP6 implementation takes a lot of time

[Former Member]

Dear Guys,

it seems that SGEN has been introduced during the EHP6 implementation (shadow instance). Now this phase is taking a lot of time.

My phase started at 15.00 and at 06.00 is still running.

The strange thing is that it's using 3 processes despite it has 12 processes available.

Someone of you experienced the same behaviour?

[former_member144433 · Accepted solution]

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

[Former Member · Accepted solution]

hello Deepika,

many thank for the great explanation. I did not notice this feature in the advanced configuration. So in the second run I will skip it for sure. It took 20 hours to complete and for me was totally unnecessary because after the upgrade I had to migrate from DB2 to ASE. So i will manually perform the abap load in the migrated system.

thank you again

[former_member208623]

Hi,

we accidentally choose option "generate ABAP Loads on shadow system during uptime" in configuration phase on a sandbox system.

Therefore SGEN starts in phase preprocessing - MAIN_SHDIMP/SUBMOD_SHD2_RUN/RUN_RSGEN. As we dont want to have SGEN running at this point in time, we manually adjusted status table of SGEN - GENSETM.

This table contains the status of the generated load within field GENSTATUS:

GENSTATUS ='X' - generated successfully

GENSTATUS ='P' - in process

GENSTATUS ='I' - open

GENSTATUS ='S' - syntax error

GENSTATUS ='E' - other error

At first we ran a few select count on field GENSTATUS after 30 Minutes

GENSTATUS = 'X' --> ~13.000

GENSTATUS = 'I' --> ~290.000

Therefore we decided to speed up this phase and scheduled SGEN as post update process

This can be done by updating field GENSTATUS.

update GENSETM set GENSTATUS = 'X' where GENSTATUS = 'I'

Regards, Christoph

[former_member93662]

Hi Experts,

I got the same issue and ended up in this blog. Thanks guys for elaborating the issue so that I could relate my issue with this one far better.

Finally got the solution for this problem,

SAP Note: 2475935 - ABAP upgrade : How to skip phase RUN_SGEN_GENER8 on shadow instance.

Refer Option#1 which fixed this issue for me.

Thanks,

Syed Hussaini

[Reagan]

Good Day

Yes I have and all you need to do is WAIT until it finishes.

If it fails then repeat the step.

Make sure there is sufficient free space in the tablespaces.

Cheers

RB

[paul_power]

Hi Bruno,

With regards to your query, you can check out this note:

1132507 - SGEN: Using maximum number of free work processes

You may also want to check parallel generation in this link:
http://help.sap.com/erp2005_ehp_04/helpdata/EN/28/52583c65399965e10000000a114084/frameset.htm

You may also monitor tablespaces as they tend to grow during SGEN and
then they will get back to normal. If you want, you can also increase
tablespaces.

You can also check the Oracle dictionary stats:

Note 838725 - Oracle dictionary statistics and system statistics

You can go to transaction RZ12 and select the group "parallel generator"
and make the relevant changes thereby increasing the number of work processes that SGEN

uses.

Regards,

Paul