Linux and Mainframe

Red Hat announced the end of service for RHEL 5. They will offer another three and a half years of security patches and critical fixes if a customer has bought the Extended Lifecycle Support (ELS).

This enterprise distribution has been in the market now for more than ten years. Now it's time to move on. Best of course would be the RHEL 7 stream, which right now is at RHEL 7.3. Every day you stay on the old release without security updates is increasing the risk of being hacked!

March 21, 2017

SHARE San Jose 2017

February 22, 2017

SUSE Linux Enterprise 12 Service Pack 2 (SLES 12 SP2) released

On November 8th 2016 eleven months after the last service pack SUSE has released the latest updated to their flag ship server distribution. SUSE also has a blog post with some more details.

The kernel level for 12.2 is kernel-4.4.21-69.1. This is a jump in the kernel version from the old 3.12 based kernel. It's the same major kernel level that's being used by Canonical for Ubuntu 16.04. And with that kernel a lot of new functionality is delivered. SUSE and IBM worked hard to ensure that for applications it behaves the same.

What's new (details see documentation and release notes):

The release notes states that SUSE now fully supports MariaDB. They have version 10.0.27 inlcuded
Networking:

For OSA the specification of a portname is no longer needed
Hipersockets can now be bridged to Erhernet
Layer2 offloads are enabled
The 10 GbE RoCE card now also supports the DAPL/OFED stack on

Encryption and security updates
Glibc has now the first set of SIMD exploitations for z13
Toolchain module updates
Full KVM host support - so you can now run SLES12 as a Hypervisor on System z an Linux boxes
....

Here is my usual summary of links to more information:

Complete SLES 12 documentation

SLES 12.2 release notes (s390x version)
z Systems / s390x specific information
release notes for High Availability Extensions (z Systems / s390x version)
release notes for SDK (z Systems / s390x version)
SUSE tuning guide updated to SP2
Whitepaper on SUSE's module concept

IBM documentation on developerworks
Docker support statement

(updated 5/2/2017)

February 16, 2017

IBM z Systems Processor Optimization Primer

For z Systems optimizations are essential to keep the consolidation ratio high and make the best use of the hardware. As more and more open source software is ported to Linux on z / LinuxONE Kevin Shum has posted his excellent "BM z Systems Processor Optimization Primer" on developerworks.

There is a long version with all the details and a shorter summary presented at last SHARE.

This is a "must read" for everyone working on compilers and inline assembly on z.

November 4, 2016

Red Hat Enterprise Linux (RHEL) 7.3 released

On November 3rd 2016 Red Hat released the next regular update to their flag ship operating system.

The kernel level for 7.3 is kernel-3.10.0-514.el7.

Here is my usual summary of links to more information:

Complete RHEL 7 documentation

IBM documentation on developerworks (7.2 version)
RHEL limits
RHEL lifecycle with the end date for the Extended Update Service (EUS)
RHEL7 package list

From a Linux on z Systems perspective the major enhancements are in the tool chain. The compiler can now can exploit the SIMD instructions of z13.

Also in September Red Hat achieved EAL4+ / common criteria certification for RHEL 7.1:

(updated 4/11/2016)

October 12, 2016

Oracle 11 R2 now certified on RHEL 7.1 for Linux on z / LinuxONE

The certification is finally done with Oracle 11.2.0.4 and RHEL 7.1. It's highly recommended that you upgrade to the latest fixpacks though. Read more in the IBM Flash or go directly to Oracle support and read the Oracle Note (requires Oracle login):

1967531.1: "Requirements for Installing Oracle 11.2.0.4 RDBMS on RH7 on IBM: Linux on System z (s390x)" - which has detailed installation instructions, which are a must read before trying to install.

As usual with Oracle certifications RHEL 7.1 is the minimal level required.

September 22, 2016

IBM Doc Buddy now has Linux and z/VM messages

IBM Doc Buddy is a mobile app that allows for retrieving explanation on IBM z error message codes. Now you can also get Linux and z/VM messages offline explained with this app.
You can get the application from Apples Appstore or from Google Play, depending on the mobile device you use.

The information is the same as in the books (note that Ubuntu and Red Hat don't have included the message numbers yet):

You first have to download the messages for the "component" you want. To do that touch the button in the upper left corner and then select the respective component. Then you can start typing into the search field and select the message of interest:

Setup screen

Select component

Get result (can be scrolled!!)

September 19, 2016

Performance whitepapers for IBM Enterprise Content Management with Filenet for Linux on z Systems

IBM has a good portfolio of Enterprise Content Management (ECM) products. One of them is IBM FileNet. Storing a lot of data and finding content is something that z Systems does really well. So after the first whitepaper concentrating on FileNet there is a new paper that adds IBM Content Navigator and IBM Spectrum Scale (formerly known as GPFS) to the mix.

This new paper is split into two parts:

The first part with the title "IBM Enterprise Content Management for Linux on z Systems Scale-Out Case Study (Part 1): Single ECM Node with XFS and IBM Spectrum Scale 4.2" is available on Partnerworld (direct pdf download).
I'll update this post as soon as the second part is available

September 12, 2016

Java performance improvements

IBM continues to improve the performance of Java on the mainframe. To show this I've taken a snapshot of the performance improvements during the latest Java releases. The operating system was a SLES 12 SP1 and this was run on a z13 LPAR with 6 cores and SMT enabled.

As you can see you there is a solid 33% percent improvement going from the first Java 7 version to the latest Java 8 SR3 FP10 version.

So the first recommendation when you are having Java performance problems with Linux on System z is to try a more advanced Java version.

September 5, 2016

Ubuntu 16.04.1 and kernel support map

End of July Canonical released the fix update for their first mainframe release. No new features but a lot of fixes, for Linux on z many installation fixes. If you are using (or planning to use) Ubuntu 16.04 LTS it's time to think about the life cycle. Here is the support map from Ubuntu Wiki:

Source: Ubuntu Wiki as of 9/5/2016, License: Creative Commons Attribution-ShareAlike 3.0 License

My recommendation is the following:

For production use stay with 16.04.1 stream for the life of the product. Plan for a check point in spring 2018 and check if you need the additional hardware enablement delivered with the 16.04.5 kernel.
For development use you probably want the latest kernel anyhow. There 16.04.2-16.04.4 are valid choices. However I'd rather upgrade everything and go with the 16.10, 17.04, 17.10 versions. This will give you the latest versions of all the open source packages as well.

June 25, 2016

Fedora 24 for IBM z Systems and Linux ONE released

The new Fedora 24 for z Systems / s390x / LinuxONE was released 6/21/2016 together with the Intel version. Thanks to the Fedora team for closing the time gap between the architectures! The kernel level is kernel-4.5.5-300.

As usual the download is available from the Fedoraproject site and the respective mirrors and known issues are covered in the wiki.

May 20, 2016

Red Hat Enterprise Linux 6.8 released

On May 11 2016 Red Hat has announced the availability of RHEL 6.8. This marks the transition into what in Red Hat's product life cyle is called production phase 2. The kernel level is now kernel-2.6.32-642.el6, for the main bug fixes see the kernel update description.

As usual there are the release notes and the technical notes in two separate documents. The complete documentation can be reached from the Red Hat documentation page (you need to select "6" on the left bar).

The IBM documentation for RHEL 6.4 on developerworks still applies for this release.

From a technical perspective the most important part are the z13 performance patches, which will make certain workloads run faster than on previous releases.