1. Highlights of Cheryl Watson’s TUNING Letter 2006 No. 6
2. IBM and Yahoo Introduce Search Engine
3. Corrections to Cheryl Watson’s TUNING Letter 2006 No. 6
4. Interview with SHARE’s President
5. Rule of Thumb for CPU Utilization
6. Online Computer Quiz
1. Highlights of Cheryl Watson’s TUNING Letter 2006 No. 6
The forty-three page 2006 No. 6 TUNING Letter was emailed to subscribers on December 13, 2006. Single issues may be obtained for $155 each from our Web site at http://www.watsonwalker.com. The following is a summary of just some of the contents of this latest TUNING Letter:
Daylight Saving Time Change
A new US law will change the rules for implementing Daylight Saving Time in 2007 for most of our readers in North America. Because this could affect any device or software program that does date calculations, we strongly recommend that you investigate this well before the first scheduled time change on March 11, 2007. Please read our article on page 35 to learn more.
System z Education
IBM is working on several projects to improve the training available to mainframe professionals. These include a SHARE project for new users, a program to encourage z/OS courses at academic institutions, and some free online training. More details can be found in our article on page 25.
Hot Flashes
On page 11 you will find an expanded version of Cheryl’s Hot Flashes session that is presented each SHARE. This sixteenth version is from the Baltimore SHARE meeting, and gives the results of the survey questions asked in August. It also describes a quick and easy way to get your older “green screen” applications converted to jazzy Web-enabled applications.
Measuring Processor Speed and Capacity
The terms MIPS, Service Units, and MSUs are all different measurements of processor speed and capacity. Most of the questions we get from our readers relate to these terms, what they represent, and how they are used and calculated. Please see the article on page 19 where we will try to make you a speed and capacity expert. We will define each of these terms, explain what they mean and how they are calculated, and show you how to convert from one to another. We will also provide answers to the most common questions we receive and pass along some recommendations.
IBM Announcements
There have been some IBM announcements since our last issue that may benefit your organization. Users of the DS8000 storage device may be able to take advantage of a new HyperPAV option that improves your DASD response time while consuming fewer resources. It does this by implementing a more dynamic management technique for the existing PAV (Parallel Access Volume) facility. We provide more details about HyperPAV on page 36. Also, tape users should read our article on page 39 to learn about a new high capacity tape cartridge.
Elsewhere in this Issue
On page 34 we mention a new IBM Red Alert that describes data loss that may occur when running HSM Recycle processing under z/OS 1.8. • Are you in the process of planning for z/OS 1.8? If so, you may be interested in some of the documentation changes that were made in that release. See page 32 for all the details.
2. IBM and Yahoo Introduce Search Engine
On December 13th, IBM and Yahoo announced a new search engine that can be downloaded and used for free. Here are some of the details as taken from the press release:
IBM and Yahoo! Inc. today introduced new, free enterprise search software with Web search services powered by Yahoo! that enables departments and businesses of all sizes to quickly and easily find, access and capitalize on information stored within organizations and across the Web.
IBM OmniFind Yahoo! Edition is a no-cost, entry level enterprise search product developed to help eliminate financial and technology barriers to intranet and Web search. Unlike other enterprise search solutions that can cost thousands of dollars to purchase and implement, the new offering from IBM with Web search services powered by Yahoo! can be downloaded for free and is simple to install and use with existing hardware.
With support for up to 500,000 documents per server, more than 200 file types and documents in more than 30 languages, IBM OmniFind Yahoo! Edition offers a unique combination of simplicity, openness, and functionality. It features a three-click installation process and takes customers only minutes to go from download to live search and information access. IBM OmniFind Yahoo! Edition also uses the open source Lucene indexing library to provide cross-platform full text indexing.
IBM OmniFind Yahoo! Edition offers advanced features such as automatic spell correction, support for synonyms and shortcuts, wildcard support to substitute for unknown characters, query reporting, and graphical user interface customization. In addition, it is fully integrated with Yahoo! Search, providing one-click access to send queries to Yahoo! web, image, video, audio, directory, local and news search services.
Although IBM has stepped into a market where there is already a lot of competition, some of the features are quite impressive. And you cannot argue with the price. To read the entire press release, visit http://www.ibm.com/press/us/en/index.wss and look for the press releases dated December 13th. Use the link http://omnifind.ibm.yahoo.net to download a copy of the search engine. You might want to investigate this to see if it provides value for your organization.
3. Corrections to Cheryl Watson’s TUNING Letter 2006 No. 6
Because of a minor typographical error that could cause undue alarm for our readers, on December 14th we emailed a replacement copy of the TUNING Letter that was mailed to subscribers on December 13th. Here is a summary of the correction that was included with that replacement TUNING Letter:
This is a replacement for the TUNING Letter 2006 No. 6 that was sent to you yesterday. There was a typo that might cause a lot of concern among readers, and it’s important that it be corrected. At the top of page 14, there was a list of servers with a note attached to three groups of servers indicating that they only support z/OS 1.4/1.5 and will therefore not be supported past March 2007. The asterisks were mistakenly added to the z800, z900, z890, and z900 servers. All of the zSeries machines (including these machines) support all current operating system releases, so this mistake may lead to some zSeries customers thinking that they need to upgrade their hardware. We apologize for any inconvenience this may have caused our readers. A great IBM link that shows operating system and hardware combinations can be found at http://www-03.ibm.com/servers/eserver/zseries/zos/support/zos_server_support.html.
Please replace the previous copy with this updated version. If copies of the previous version have already been distributed within your organization, please replace these with the new version, or make your readers aware of the original error.
Also, reader Robert Justice pointed out an error with the next-to-last paragraph on page 18. We mentioned an operator command that is useful for tuning XCF, but the command we showed was incorrect. The command that you should use is “D XCF,CD,CLASS=ALL.” This correction was not included with the revised edition sent out today, so please make note of this change.
4. Interview with SHARE’s President
We think that SHARE is a wonderful user group, and that it provides a lot of benefits for those organizations that are fortunate enough to be able to participate. Even if you cannot attend regularly, there are some resources on their Web site (http://www.share.org) that are available to all.
We recently read an interesting online article that contained an interview with the new President of SHARE, Martin Timmerman. You can read this article yourself using the link http://www.esj.com/news/article.aspx?EditorialsID=2301. Martin shares some interesting observations about industry trends, and how SHARE plans to adapt their program so that they can provide the necessary training to remain relevant. If you have any interest in SHARE, you will enjoy reading about the vision of its new president.
5. Rule of Thumb for CPU Utilization
Anyone who does performance monitoring knows about ROTs (Rules of Thumb), and uses them daily to help determine the health of their systems. But rules of thumb have to evolve over time, as technology and applications change. In our latest TUNING Letter, we included an article called “Rotting ROTs,” where we looked at some of these rules, and tried to determine if they are still relevant. One of the things we decided is that (in some cases) they are not. For example, the ROT for CPU utilization used to be that you should run your processors at 80% busy or less for best performance.
Now we are hearing from some experts who say that it is best to run processors as close to 100% as possible. The Workload Manager is now sophisticated enough to manage the workloads correctly, even at 100%. Our opinion is that unused CPU cycles can never be regained, so you should use those cycles if your performance doesn’t suffer.
It did not take us long to hear from readers who do not share our opinion. They were armed with their own studies and reports showing that running at full utilization would be damaging to some of their critical workloads.
We agree that there are exceptions to every ROT, and that this ROT may not work for all environments. But we hear from other readers who say that they run close to 100% utilization with few performance problems. It depends on many factors, including your applications, your configuration, and your Workload Manager controls.
We appreciate those readers who took the time to research their own environments and provide us with their results and their opinions. This is an interesting subject, and we plan to address it further in future TUNING Letter issues. We will make sure to mention those environments where following a particular ROT might not be a good idea.
6. Online Computer Quiz
Our resident Web guru Tom Walker recently found an interesting online computer quiz. Follow the link http://www.ccrnp.ncifcrf.gov/ComputerMuseumQuiz, and see how well you do.
There are 29 different questions, and each one will show you a picture of some ancient computer relic (punched card, floppy disk, etc.). When you think you know what it is, press the “Get answer” link, and it will display the answer. Sadly, we did pretty well on this, and we suspect that many of our readers will also.
Stay tuned!