Local client copy

[Former Member]

Hi,

I am running a local client copy using 5 parallel processes.

Suddenly i can see after sometime the parallel processes reduced to 2 and the client copy is very slow now.

Is it recommended to lock the source client before client copy for better performance and any other prerequisites need to be followed?

[Former Member · Accepted solution]

Hi

there are two reason why you parallel work process are reduced to two .

1. generally Client copy runs in background and it schedule the job of Class C while running the same if any other background job with higher class needs to be run SAP will deallocate your work process and give it to other Work process

2. solution to this is as followes

- try to schedule the same in night

- in night operation mode increase the value of background process and reduce the dialogue work process if it suits your project requirement.

- have adequate space in table spaces

3. and there is no need to lock Source client .

all the best

Regards

Dishant pathak

[divyanshu_srivastava3]

Hi Padmini,

Did you check the generation of archive logs ?

If you are running with 5 parallel process then you should check the logs and dialog processes for the issue.

A good practice is to lock the source if you can during client copy so thar changes are not made.

Refer

https://help.sap.com/saphelp_nw04/helpdata/en/69/c24c4e4ba111d189750000e8322d00/content.htm

Regards

[Former Member]

Hi Padmini,

If you use parallel processes, dialog processes are used even if the job is scheduled in the background. Please check RZ12 RFC server group for parallel processing.

Parallel processes are only used during the actual copying phase.They are not used during the analysis and post-processing phases.  The resource management only assigns a limited number of processes to the client copy.

Towards the end of the copying phase, the number the processes is reduced as the worklist is divided but individual processes are still copying very large tables.

Also, please refer to the following notes.

541311 - CC-INFO: Parallel processes FAQ

552711 - FAQ: Client copy

Thanks

Adil

[Former Member]

Hi Adil,

Thanks for your reply.

RZ12 parallel process i have checked and it is fine.

Yes you are right, the client copy is actually in its last stage with few tables remaining to be copied.

Currently it is running for swwloghist and sww_wi2obj  which are very huge in size but it is very slow.

When I started client copy it was using 5 parallel processes and speed was good but when it finished almost 90% of client copy the parallel processes reduced one by one and now there are only 2 active.

Is there any possible way to speed up client copy? I learnt that increasing rdisp/max_wprun_time parameter will help but system restart will be needed.

[divyanshu_srivastava3]

Hi Padmini,

Are these the EDI* tables ?

rdisp/max_wprun_time is used to increase the timeout and is dynamic. You can change from RZ11 with reboot. But that would not really help.

As I told you above to check logs and processes for issues.

As you know the parallel processes are dynamically generated during client copy. The factor that influences copy speed is database state and source client. Which you can only wait until it completes.

Regards,

Divyanshu

[Former Member]

HI,

I had to stop the client copy as the above mentioned table was taking so much time. and then I restarted it excluding that table and it got completed successfully.

Anyways i would like to know if there is any minimum number of parallel processing that is by default required for doing client copy which has huge size like 1 TB?

Thanks

[Former Member]

Dear

first you increase you dialog process and background process those are only use at time of local client copy. if they are enough available for local client copy. and users if you are not lock the users. when it writes long table it consumes all the process one by one so the parallel process are reducing

and keep orachive log in off mode by this you copy big client also

Regards

[divyanshu_srivastava3]

Hi Padmini,

For local client copy, you have advance function which you can enable but you need to be smart enough to understand it also, there is as such no minimum value to it.

Read: Parallel Processing Jobs with Asynchronous RFC - Computing Center Management System (BC-CCM) - SAP L...

which comes from SAP note - 541311

Now, how many cores you have, how much load you have, your database state, all this taken into account for throughput.

As per above note:

If the target client is empty and the source database in good shape (updated statistics, little disorganization), you can expect a throughput of approximately 500MB to 1GB per hour and process on a modern database.That is, approximately 4GB to 8GB with 4 CPUs and 8 processes.

Since this is local copy, you can reduce the throughput and add for no network delays.

Also, you can check advance from SCCL

Regards,

Divyanshu