Consultants Study

ISX Study by Consultants at Solution ArchiTECHS, Inc.

ISX Product Review
ISX Performance

ISX Product Review

Solution ArchiTECHS, Inc.
6008 Pratt Street Tampa, FL 33647
Phone 813-910-7775

Date: 02/17/2000
To: Gene Josephs
From: Rance Blair
Subject: ISX Product Review

Dear Mr. Josephs,

I have reviewed all the ISX product documentation and discussed ISX with the developers. I concluded that ISX would be of great value in a VSE/ESA to OS/390 migration project. A conversion effort entails many aspects; program code and JCL conversion, staff training and education, project staffing, data migration and movement between systems, hardware/software resources and the installation and customization of OS/390. Another area of concern during a migration is system performance. By using ISX, a customer can significantly simplify the hardware/software resources and data migration effort required in the migration project without any performance impact. The exploitation of OS/390 resources by ISX to improve VSE/ESA guest performance is outstanding.

Typically sites will use VM/ESA or an LPAR to accommodate OS/390. Having recently participated in 2 VSE to OS/390 migrations, I prefer the LPAR approach versus using VM for 2 reasons:

In LPAR mode, OS/390 is running natively on the hardware and not as a guest of VM. While this can consume additional hardware resources, it is the final configuration that will be running in a production environment after cutover.
VM adds a layer of complexity because now there are 3 operating systems to support instead of 2. There is a large learning curve for the technical staff to install and support OS/390. By removing VM from the picture, there is one less operating system to worry about.

ISX is a direct competitor to VM/ESA with ISX having many advantages. The following is a summary of the benefits I see from using ISX during a conversion effort.

VM/ESA versus ISX with OS/390

ISX provides many of the same functions as VM, such as virtual device support. This could reduce the hardware resources required during conversion.
ISX can emulate FBA devices for a VSE/ESA guest.
ISX is a product running as a subtask of OS/390. This is a much simpler environment to install and maintain than VM, which is another operating system.
ISX utilizes OS/390 resources for device and network I/O and subtasking. This could provide a significant performance boost for a "’typical" workload of a VSE/ESA guest.
The data transfer capabilities built into ISX will ease dataset movement between systems. Data transfer is a batch process on OS/390 and can therefore be scheduled using an OS/390 job scheduler or automation package.
ISX will easily support both conversion strategies ( Kernel / Incremental and Mass Conversion), with lower overhead than VM.
All OS/390 facilities are available to the conversion process such as Workload Manager, Systems Managed Storage, SAF Security, Automation and Job Scheduling.
New workloads can be developed for the OS/390 environment while the conversion project is in progress.
ISX definitions/configurations are straight forward and easily set up and maintained. The ISX subtask can be stopped and restarted without requiring an IPL of OS/390. Multiple ISX subtasks are also supported.

Based on my experience and analysis of the ISX product, ISX is an extremely valuable tool for VSE customers planning to migrate to OS/390. ISX will provide VM/VSE customers with an overall direct lower cost migration choice while offering improved performance. ISX also has great value as a workload consolidation tool, allowing a customer to consolidate VSE/ESA workloads under OS/390.

Sincerely,
Rance Blair, President
Solution ArchiTECTS, Inc.

ISX Performance

Solution ArchiTECHS, Inc.
6008 Pratt Street Tampa, FL 33647
Phone 813-910-7775

Date: 02/17/2000
To: Gene Josephs CEO IIS,LLC
From: Rance Blair President
Subject:Performance Review of ISX with VSE/ESA

Dear Mr. Josephs,

Based upon performance input from the ISX development team regarding a VSE/ESA system running as a guest of ISX with OS/390, it is my conclusion that the OS/390-ISX environment is:

superior to a VM environment with VSE/ESA and
superior to a LPAR environment operating VSE/ESA

Since ISX runs as a task of OS/390, any guest running under ISX will realize performance benefits of efficient I/O for DASD and Network devices, as well as being able to exploit multiple processors.

On the surface, the performance numbers appear too good to be true, but once you understand how ISX uses OS/390 resources, the numbers make perfect sense. While overall CPU utilization will increase, the completion times for batch work and transactions in the VSE/ESA system actually decrease. Please keep in mind that our discussion was concerning a "typical" workload of online transactions and batch processing. It should also be stated here that ISX achieves its performance benefits by using standard and documented OS/390 facilities and interfaces. Therefore, ISX compatibility with new releases of OS/390 should not be an issue.

ISX is a very exciting product and opens up new possibilities for VSE customers wishing to migrate to OS/390.

Please let me know if there is anything else I can do for you.

Sincerely,
Rance Blair, President
Solution ArchiTECTS, Inc.