1. Highlights of Cheryl Watson’s Tuning Letter 2008 No. 1
2. New IBM Red Alert for JES2
3. SHARE
1. Highlights of Cheryl Watson’s Tuning Letter 2008 No. 1
The forty-eight page 2008 No. 1 Tuning Letter was emailed to subscribers on February 21, 2008. You may visit our Web site at http://www.watsonwalker.com to obtain single issues for $155 each. The following is a summary of just some of the contents of this latest Tuning Letter:
Performance Results
The main two articles in this issue deal with understanding the performance impact of changes in your configuration. The zPCR Experiences – Part 2 article shows how the addition of new special function processors, such as zIIPs and zAAPs, can impact the general purpose CPUs. The article shows the importance of evaluating the impact on your system before you actually exploit the new facilities.
The second article, z/OS Performance, shows how IBM determines the impact of a new release of software, such as z/OS 1.8, as well as the impact of exploiting new facilities. IBM’s free tool, SoftCap, can help you identify the potential impact for your own site. This article shows the results of IBM’s benchmarks for z/OS 1.7 and z/OS 1.8. One of the more important trends is that each new release of z/OS seems to be using less CPU rather than using more CPU as with earlier releases.
News
One of the more important items in this issue is the addition of a new WLM function called Blocked Workload Support, which is especially important for DB2 users who run at 100% busy. You have to take certain actions to implement this new support. We include three very important WLM APARs starting on page 5. Our APAR section also includes several New Function APARs, as well as many HIPER APARs that are important to address. We highlight several of the HIPER APARs that we feel are especially important, such as the one that reports more DB2 usage than is physically available in the machine! I especially like the Net item about Resolving Common z/OS Problems.
Q & A
In our Q & A, we include questions and answers about Linux and z/VM, DB2 Page Fixing, and hints for new z/OS users.
Elsewhere in This Issue
We’ve replaced our What’s New section with one called IBM Announcements. In this issue we discuss the latest zSeries chip, which is 2.5 times the speed of the fastest z9 processor. · Cheryl’s List describes a new IBM Red Alert for QSAM. · SHARE’s zNextGen project for new z/OS users is an amazing project, and one that could provide significant help to anyone in your staff who is new to z/OS.
2. New IBM Red Alert for JES2 on z/OS 1.9 Systems
On February 2, 2008, IBM created a new Red Alert warning of potential data loss from JES2 spool volumes if you IPL a z/OS 1.9 member in a JES2 MAS while any spool volumes are draining. Here is the description, as taken from the alert:
DESCRIPTION:
Users may experience data loss from JES2 spool volumes when IPLing a z/OS 1.9 member in a JES2 MAS while any spool volumes are in a draining status. JES2 DISASTROUS ERRORS (DISTERRs) such as CBIMPL4 and CBIMPL12 DISTERRs will occur as JES2 processes jobs on the affected volumes; these jobs and their data will be lost.
Please see APAR OA23615 for additional details.
RECOMMENDED ACTIONS:
Do not IPL a 1.9 member in a JES2 MAS while any spool volumes are in a draining status.
– To resolve this issue, IBM strongly recommends installing the ++APAR or the PTF once it becomes available shortly, on all 1.9 systems prior to the next IPL of any 1.9 members. The fix can be installed one system at a time.
– If it is necessary to IPL a 1.9 member before the fix can be applied, make sure no spool volumes are draining by using the $DSPL command to locate any volumes with STATUS=DRAINING. If any volumes are draining, issue $SSPL(volser) to take it out of DRAINING status and make it ACTIVE, prior to IPLing any 1.9 members.
See OA23615 for further information.
The APAR is marked as closed, but a PTF isn’t yet available.
You can use the 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. SHARE
I’m getting ready for SHARE in Orlando February 24th to 29th. I hope to see you there. You can see the sessions and presenters at http://www.share.org. I’ll be speaking at three sessions. My major presentation is my Hot Flashes session (#2509) on Friday at 9:30 am. I’ll also be part of two panels. The first is session 3105 on Monday from 12:15-1:15 – zNextGen Lunchtime Panel Discussion: The Tips Your Mentor Forgot to Mention. The second is session 2549 on Thursday at 4:30 pm –Meet the Experts: WLM, Performance and Capacity Planning Topics. See you there!
Stay Tuned!