1. Cheryl Watson’s TUNING Letter 2006 No. 4
2. Four New Red Alerts
3. Important CICS Fix
4. Specialty Engine Pricing
5. SHARE in Baltimore Proceedings Available
6. Corrections to Cheryl Watson’s TUNING Letter 2006 No. 4
1. Cheryl Watson’s TUNING Letter 2006 No. 4
The forty-seven page 2006 No. 4 TUNING Letter was emailed to subscribers on August 25, 2006. Single issues may be obtained for $135 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:
Preview of z/OS 1.8
Several of our informal surveys have shown that most organizations are running at least one copy of either z/OS 1.4 or z/OS 1.5. If this applies to you, make note that IBM currently plans to drop support for both of these releases in March of next year (2007). That’s only slightly more than six months away! You should start planning soon for migration to a more current release – either the current z/OS 1.7 release or z/OS 1.8, which will be available in September. Users of z/OS 1.4 can migrate as far as z/OS 1.7 in one step. It is planned that users of z/OS 1.5 will be able to migrate as far as z/OS 1.8 in one step. If you are trying to decide between these two current releases, it might be useful to know what new features are planned for z/OS 1.8. We have put together a useful preview of z/OS 1.8 that starts on page 27. We start out with the enhancements planned for the Base Control Program (BCP), and include important components such as the Workload Manager, the System Resources Manager, RMF, ISPF, SCLM, JES2, JES3, and SDSF. Then we look at improvements that are planned in the areas of Data Management, Networking, Security, and z/OS UNIX. We also summarize the IBM Statements of Direction that accompanied the preview announcements. These statements are important because they indicate technologies and features that IBM plans to introduce or phase out in future releases. Knowing about these intentions early could save your organization a lot of time and money. We also provide links to Web resources that can help you plan for z/OS 1.8.
ESCON and FICON Tuning
Many organizations are moving towards FICON channels because of the superior performance they offer when compared to the older ESCON technology. But how do you go about measuring and tuning these channels? Can we use the same old rules of thumb that we have always used for ESCON channels? Are there new factors that come into play when we configure FICON channels? What performance rules are the same for both channel types, and what rules are different? Please see page 14 whereBill Eagle of EMC Corporation answers these questions.
SHARE in Baltimore
We just returned from the latest SHARE conference, and we pass along a few tidbits from the trip starting on page 24. There are many excellent sessions at each SHARE conference, but we do our best to glean the real gems and pass them along to our readers. You will find just a summary in this issue, but we will have more to say in future issues.
Elsewhere in this Issue
If you are planning to install one of the new zIIP specialty processors, there is an important fix that you need to install first (see page 4). In that same section you will find our usual collection of recommended fixes that you should review. • Velocity goals are useful for many types of workloads, but they require more maintenance than other types of goals. We pass along some good advice, and also refer you to an excellent IBM paper on the subject (see page 8). • Those who order one of the new System z9 Business Class processors will get a price break on the specialty processors, but there is one exception that might surprise you (see page 42).
2. Four New Red Alerts
IBM will issue a Red Alert when it finds a software problem that can be particularly disruptive or destructive. Since the previous issue of Cheryl’s List, IBM has issued four new Red Alerts – three of them so far in the month of August! Here are the issue dates and titles for each of these four new alerts:
28Jul2006 – All users of z/OS and z/OSe 1.6 zIIP Web Deliverable (JBB77S9) and z/OS and zOSe 1.7 zIIP Web Deliverable (JBB772S)
10Aug2006 – IMS/VSAM interface problem affecting IMS users of VSAM Hiperspace buffers
24Aug2006 – Unpredictable errors running z/OS 1.6 with z/OS and z/OSe 1.6 zIIP Web Deliverable (JBB77S9)
25Aug2006 – Media Manager IO errors and potential data loss if using MIDAWs
In the latest issue of the TUNING Letter, the first two Red Alerts are identified as such, and are documented on pages 4-5. The APAR associated with the third Red Alert (OA17458) is mentioned in our SHARE Highlights article on page 25, but had not been identified as a Red Alert when we published the TUNING Letter. The fourth Red Alert is not mentioned, but is described by this APAR:
OA17844 (z/OS 1.6+, OPEN 22Aug2006) – For SMF Receive IEE393I SMF Physical I/O Error … D/T2094 for HFS Receive IGW027E HFS xxx SYNC I/O Error. Users may receive error message IEE393I while SMF is trying to write to an SMF data set. Also, message IGW027E may be issued when an error occurs while trying to synchronize an HFS data set. In both cases, the users were running on a System z9 processor with the MIDAW facility enabled, and either APAR OA15958 or APAR OA16728 had been applied. The local fix is to disable MIDAW support with the “SETIOS MIDAW=NO” operator command.
Use the Web link http://www.ibm.com/servers/eserver/support/zseries/ to view the current Red Alerts. Just select ‘Red Alerts for System z’ from under the ‘Popular links’ heading to display the current entries. Once you are on this page, you can also register so that you will be sent an email when a new Red Alert is issued. We strongly believe that at least one person from every organization should be subscribed to this service.
3. Important CICS Fix
IBM has issued the following APAR that applies to CICS 3.1 users that are running Web-enabled applications:
PK26453 (CICS 3.1, 2Aug2006) – SOS, CICS Storage Creep in ECDSA, Subpool WBGENRAL. A storage creep and possible SOS condition can occur in the ECDSA WBGENRAL subpool. This may happen if a program issues a WEB STARTBROWSE command, followed by one or more READNEXT commands, following by a return to CICS without issuing an ENDBROWSE command. The storage obtained during the READNEXT calls is obtained out of the WEBGENRAL subpool in ECDSA, and is not freed at task termination if the application does not free it. A local fix is to correct the application program so that it issues the ENDBROWSE action before returning control to CICS.
See the text of the APAR for more specific information about the sequence of commands that causes the error conditions. Thanks to Jerry Urbaniak of Acxiom for alerting us to this problem.
4. Specialty Engine Pricing
In TUNING Letter 2006 No. 3 we described recent enhancements to the System z9 line of processors, including the new System z9 Business Class processor (z9-BC) and the enhanced System z9 Enterprise Class processor (z9-EC). One of the things we mentioned was that the price of specialty engines for the z9-BC had been reduced from $125,000 to $95,000 per engine (see page 19).
Since that time, we have been contacted by a reader whose organization was quoted a much different price for an ICF engine on a z9-BC processor. We have confirmed with IBM that the price of $95,000 for a z9-BC specialty engine does not apply to ICF processors.
We have corrected the original article so that there will be no misunderstanding of this point, and the updated article will appear on the collection CD-ROM that will be issued in early 2007. We have also included a pricing update in our latest issue (see TUNING Letter 2006 No. 4, pages 42-43).
5. SHARE in Baltimore Proceedings Available
Even if you were not able to attend the latest SHARE conference, you can still browse the listings of the sessions presented, and download or browse a copy of the session handouts. Although you need to be a registered user to access the proceedings from previous conferences, it appears that the proceedings from the latest meeting (Baltimore; August 13-18, 2006) are available at the SHARE Web site (http://www.share.org) without requiring any special authorization to access them.
From the main SHARE page, select the “Baltimore Proceedings” option on the left-hand side. From the Proceedings screen, you can browse the sessions by session number, subject track, program/project, or the name of the speaker. There is a search function as well, but it doesn’t always seem to find all the sessions it should.
For each session listed, there will be a session number and title. If a handout is available for the session, an icon of a paperclip will appear after the title. When you select a particular session, you will see more information, including the session abstract and a listing of the speakers and their organizations. The names of any attached files will also be listed (they are all PDF files), and they can be browsed or downloaded by clicking on the file name.
This is a wonderful resource, and we’re grateful that the SHARE organization is making the proceeds of their latest conference available to the entire community. If you did not get the chance to attend SHARE, you can still benefit by looking at the materials presented by dozens of speakers in hundreds of sessions.
6. Corrections to Cheryl Watson’s TUNING Letter 2006 No. 4
In our latest TUNING Letter we included a summary of the features provided by z/OS 1.8 and z/OS.e 1.8 (see TUNING Letter 2006 No. 4, pages 27-41). In the first bullet item on page 27, we described the enhancements that allow you to install more processor real memory. At one place we stated that a previous maximum was “128 MB,” and in a second place we stated that a new maximum was “256 MB.”
As more than one reader pointed out, both of these should have been GB to represent gigabytes of memory. We will make this correction before this issue is placed on the collection CD-ROM at the end of the year.
Stay tuned!