DDM Files are very slow

[Idej369]

We have been running two software packages on one iSeries (V6R1M0) for several years, and we have several programs (RPG) that use files from both packages. Due to a recent software upgrade, one of the software packages had to be moved to a new iSeries (V7R1M0). Unfortunately, one package has to run under V6R1M0, and the other V7R1M0. We have created several DDM Files across the two systems to allow us to run the programs that use files on both systems. While they do run, accessing the DDM Files is very slow.

Is there a way to optimize the systems in order to get better performance when using DDM Files?

[EmmanuelW1]

You don't say how the two systems are connected, which may be related to the speed of accessing the remote file.

Cheers,

Emmanuel

[Idej369]

Hello Emmanuel:

Thank you for the prompt feedback. Both of the iSeries Machines are connected to our Network via Ethernet. We created an APPC Controller on each Machine with the Link Type of *HPRIP. When we create the DDM Files, we specify a Type of *IP and key in the IP Address of the Remote Machine.

As a test, I wrote an RPG program and ran it on both systems, one using the Physical File and the other using a DDM File. The File had just over 195,000 records. All the program does is read the file and write a record to a Spooled File. It takes less than five seconds to run the program on the Local Machine, and that includes the time that it takes to answer the "Maximum number of records reached" message on the Spooled File. The same program takes over 15 minutes to run on the Remote System.

Any help that you can provide on this will be greatly appreciated!

[EmmanuelW1]

There are a lot of settings involved that may impact the speed of the connection. If you have active support with IBM, I would open a PMR on this to troubleshoot the issue. It may be a simple change to a setting in the controllers, the Ethernet line configuration, etc.

Have you tried copying the remote file to the local machine? Is that also unexpectedly slow?

Cheers,

Emmanuel

[Idej369]

Emmanuel:

Yes, we copy some of the relatively "static" files over to the remote system to be used by some programs; however, this does not work for files that are frequently updated and/or files that are updated by the programs on the remote system.