In-Depth
IBM Preps z/VM Overhaul
z/VM 5.3 might still be five months away, but many VM programmers are already licking their lips in anticipation
Last week, IBM Corp. announced a new rev of its mainframe virtualization technology, z/VM version 5.3.
Although it isn’t slated to ship until June, z/VM 5.3 sounds like it’ll be worth the wait—and merits a preannouncement five months before the fact. When it ships, z/VM 5.3 will deliver scalability and security improvements, expanded processor support, and a host of other features.
Many z/VM users are anxiously awaiting the release. "I would say that IBM delivered exactly what I expected. The developments are all along the lines of improving guest support, primarily aimed at Linux," notes Jim Bohnsack, a z/VM programmer with an Ivy League educational institution. "The improvements will allow more guests with the enhancements in CP-Linux guest cooperation and communications. The security enhancements—such as LDAP support, mixed-case passwords, and pass phrase authentication—should be well received. Replacing the old RACF 1.10 is long overdue."
In addition, Bohnsack says, the improvements IBM will deliver in z/VM 5.3 demonstrate that "VM development is right on track"—from the perspective of VM boosters such as himself, of course. "VM has developed into a rock-solid guest hosting platform. There may well be issues or features that are missing, but from my standpoint as a mainframe VM systems programmer rather than a Linux sys admin, I think that the path IBM has taken is right on course."
z/VM 5.3 will build on capabilities IBM delivered last summer in its predecessor, z/VM 5.2. It’ll boast enhanced memory and processor utilization features, such that a single z/VM partition will be able to host LPARs with more than 128 GB of real storage and up to 32 processor units (PU)—a 33 percent increase over z/VM 5.2, officials point out.
In addition, z/VM 5.3 will deliver improved guest support for specialty processor engines, such as the zSeries Application Assist Processor (zAAP) and zSeries Integrated Information Processor (zIIP); a z/OS testing environment for simulating specialty processors; a new LDAP server and RACF feature, including support for mixed-case password phrases; availability of RSCS FL530 as an optional IPLA feature; enhanced virtual network support; and improved support of IBM system and tape storage devices.
Processor Restrictions
The salient point, of course, is that many VM shops are still coming up to speed on z/VM 5.2. Those that are generally like what they see—although some lament z/VM’s rigorous hardware requirements.
"We are currently in the process of upgrading our mainframe from a 9672/x27 to a Z9, and that requires upgrading our out-of-service z/VM 4.3 to z/VM 5.2 because we started this project when 5.2 was the current release," comments Max Singley, technical services project leader with a food services company based in the Southeast.
Singley’s employer is running VSE 2.1.7 under z/VM and plans to upgrade to Big Blue’s new z/VSE 3.1 as soon as "we get the new Z9 and z/VM 5.2 in production" and fully stabilized. He says he’s impressed with both z/VM and its complementary Z9 powerplant.
"We are very happy with every aspect of z/VM 5.2 with the exception of having it drop support for our older processor, which was still quite functional for our business. We did not find it particularly beneficial to have to pay for a new processor with basically the same capabilities as our old processor simply to regain Z/VM support, but ultimately I'm sure it will position us to utilize some new functions that could help the business units."
Ditto for Ron Schmiedge, a senior analyst with a global outsourcing provider. Schmiedge doesn’t have much to say about z/VM 5.3, except to note that, like its version 5 predecessors, it’s restricted to newer 64-bit mainframe processors. "z/VM 5 requires a certain minimum level of processor to run, one that supports [a] 64-bit architecture. We have to upgrade our hardware—arriving this week—before we can do anything with z/VM 5," he indicates.
On balance, VM pros seem willing to accept that platform’s processor restrictions. Singley, for his part, says he certainly doesn’t have any hard feelings in this regard. "The 9672 lived up to its billing as being able to grow with the business and it simply lasted too long, I suppose, for IBM's software gurus to support it," he says. "[W]e are very happy with the Z9's connectivity [features] and z/VM 5.2 has been relatively problem-free in our testing."
If anything, Singley says, he wishes IBM would revamp its z/VM support. "The only other negative point … is [that] the Level-1 phone support personnel are generally English-challenged and difficult to understand. On top of that, mainframe-related software seems to be an entirely unknown world to them," he concludes. "I wish IBM would come up with a better support scheme for English-speaking customers and mainframe software users."
Not everyone likes what IBM is doing with z/VM, of course, including Ed Martin, a VM programmer with an Ohio-based health care provider network. As IBM has matured VM, it has also dropped support for core VM applications and services. It’s in this regard, Martin gripes, that his employer has been left holding the bag.
"I would love to go to z/VM 5.3, but IBM—again—is forgetting it customers," he argues. Martin’s problem? Big Blue no longer offers VSE/VSAM for VM. "We have a major application on z/VM that accesses VSE VSAM files, parses the data to a 4GL NOMAD2, and then sends that data back to PC using HTML," Martin says. "Until I can come up with another solution, we will [either] stay on z/VM 4.3 or … attempt to migrate the VSE/VSAM for VM."