AIX 7.1 moves forward to Power7 iron
And backward to older Blue boxes
A new server lineup needs a new operating system to match it, and so next month will see the debut of AIX 7.1 from IBM. And about a month earlier than expected, too.
AIX was always the laggard when it came to commercial-grade Unixes, far behind HP-UX from HP and Solaris from Sun Microsystems. And that, along with some pretty pathetic Power-based server iron, meant that HP and Sun controlled the Unix market.
But a decade ago, IBM got its Power server act together at exactly the same time that Intel's Itanium woes started hurting HP, and Sun's hubris screwed up the UltraSparc III server launch. IBM got very respectable dual-core Power4 processors out the door, and started adding capacity-on-demand and virtualization features to AIX — capabilities that that HP and Sun systems already had. Combined with very aggressive price cuts on systems — the starting negotiating price was 50 per cent off, and it went down from there pretty quickly if it was a Sun or HP takeout — the software enhancements made IBM a relatively safe alternative.
The sad irony these days is that you could make an argument that IBM's Power Systems are the only safe Unix bet when what the IT market really needs is three strong players. Oracle will eventually get its Sparc and x64 server act together, and HP will persevere with Itanium for HP-UX.
There is still room for improvement for IBM's AIX, as there is for every operating system, but the big gut-wrenching changes for AIX were put to bed between AIX 5.1 and 6.1. By comparison, AIX 7.1 is a modest upgrade in functionality that uses the same packaging that IBM has been tweaking with the AIX 6.1 release.
AIX and its companion PowerVM hypervisor, which has been upgraded to the 2.2 release along with AIX 7.1, has logical partitioning as well as workload partitions — IBM's Solarisesque riff on the virtual private server theme — for virtualization. IBM has live partition mobility to move running logical partitions (LPARs, in the IBM lingo) from one physical machine to another, and live application mobility to scoot workload partitions (WPARs, of course) around a pool of networked machines.
PowerVM can scale an LPAR from as small as 1/10th of a processor core (called a micro partition) on a Power System all the way across all 256 cores and 1,024 threads in the full-bore Power 795 machine that was announced this week.
LPARs can be allocated and deallocated dynamically, and PowerVM has features to automatically load-balance LPARs and WPARs as need be in a pool of systems. LPARs can be dedicated to specific resources, or thrown into a shared resource pool where their quality-of-service settings compete for resources.
The LPARs can be hooked into power-management features of the Power Systems iron so processor cores, memory, and other components are shut down as they are not needed, corralling LPARs and WPARs on as few physical components as possible, thereby saving energy. The Power Systems machines have hot-add and hot-remove processor, memory, and I/O with the AIX operating system running, and AIX 6.1-included memory compression as well.
All of these features took the better part of a decade for IBM to add to AIX, and were absolutely necessary for AIX to be a modern operating system. Many of these features were nicked from IBM's proprietary OS/400 operating system, but the Unix people in IBM's Austin, Texas, development lab will never cop to it — just like they'll never really admit that it was the AS/400's Rochester, Minnesota, lab that created the first several generations of the 64-bit Power chips that made it possible for Big Blue to not be an also-ran in the Unix business.
And those wickedly high prices IBM charged for AS/400 and iSeries hardware and software in the late 1990s and early 2000s are precisely what allowed IBM to sell RS/6000 and pSeries hardware at 50 per cent or less of list price and not go broke. IBM screwed one customer base to acquire another — and while that strategy worked as far as quarterly results go, it's kind of stupid when you consider that AS/400 shops were IBM's most loyal customers and about half of its enterprise customer base.
But back to AIX 7.1. Its most important feature is that it is binary compatible with AIX 5.X and 6.1, which means that Power Systems shops do not have to recompile their applications to run them atop AIX 7.1. The latest IBM Unix runs on any machine that uses the dual-core PowerPC 970, Power4, Power4+, Power5, Power5+, Power6, Power6+, or Power7 processors. IBM currently still supports AIX 5.3, which dates from 2005's Power5 generation and which included the Virtual I/O Server and micro-partitioning for AIX for the first time. According to Jeff Howard, director of marketing for IBM's Power Systems division, IBM will continue to support AIX 5.3 until early next year, and indeed, that vintage operating system is supported on current Power7-based machines.
But AIX 5.2 is not, and this is a problem, since it's still out there in pretty large numbers in the RS/6000, pSeries, and System p installed base. So with AIX 7.1, IBM has tweaked its WPAR virtual private servers so they can take a backed up instance of AIX 5.2 and its applications and suck it into a WPAR and run it unchanged.
WPARs use a single, shared AIX kernel and file system across virtual machines instead of logically isolating whole AIX instances inside of partitions to create virtual machines, and this is exactly the kind of thing to which they are well-suited — and moving to new hardware while not changing software is something customers love to do. Howard won't say if a future release of AIX 7 will support AIX 5.3 WPARs, but obviously it will unless IBM has lost its mind.
The AIX 5.2 WPAR support on AIX 7.1 has some limits. IBM's PowerHA clustering cannot span multiple WPARs and cluster them, and IBM's workload-management tools don't work in managing these AIX 5.2 WPAR instances as they did on the real AIX 5.2 machines. For some reason, the NFS file system is also not supported within the AIX 5.2 WPAR; the JFS2 file system is. There are limits to the mobility of the AIX 5.2 WPAR as well.
The AIX 5.2 WPAR feature for AIX 7 carries an additional fee atop of the per-core AIX fees. It costs $60 per core on small Power machines, $170 per core on medium machines, and $310 per core on large machines. If you want the AIX 5.2 WPARs to be mobile, you have to buy PowerVM Workload Partitions Manager for the AIX 7.1 Express or Standard Edition, or get AIX 7.1 Enterprise Edition, which includes this tool as part of its bundle.
Next page: Cranked-up core coverage
AIX and Oracle
".. and it meant for example, you could not move your Oracle 8i database running on an p680 on AIX 4.3 over to a p690 on AIX 5.1 without also moving from Oracle 8i to Oracle 9i. "
Yes there was a change in the 64bit execution format from 4.3.3 to 5.1 But hey it's 10 years ago, and to be honest the number of 64 bit executables back then was... well... basically Oracle. So It's not like it was a big problem.
Now the problem with Oracle version 8 was that Oracle never released a 64bit 8.1.X or even 9.0.1 for AIX 5.1. Only a 9.2 and newer. But it was no problem taking your 32bit Oracle 8.1.7 and moving it from AIX 4.3 to 5.1, as long as it was the 32 bit version of 8.1.7. I've seen lots of 8.1.7 run on AIX 5.3, I've even seen some 7.3.4 ones. It seemed that Oracle wanted IBM to force their customers that ran Oracle on POWER to do an Oracle upgrade. It's always smart to make others make money for you.
With regards to Containers, Solaris simply stole it before AIX did :)= I do think the AIX implementation where it's more or less an extension of the workload manager is nice.
Now the good thing about AIX is the fact that all the layers in the solution stack are one of the best on the marked. One component might not be the best but at least then it's second. And it's also a honest OS. It doesn't try to a lot of things, it's simply a UNIX made to run on big RISC servers.
And that is perhaps Solaris'es biggest disadvantage, that there are serious weaknesses in the stack, perhaps the biggest being Oracle. And that is a damn shame.
64 bit (in)compatibility with AIX 5.1
I was going to enter a long, essay type reply to this when I realised that it wasn't worth it.
I was caught by the Oracle 8i to 9i problem (but on Winterhawk SP/2 nodes, not p690's), but I reckoned that this revolved around the lock kernel extension (read device driver) that Oracle added to AIX. There was an IBM documented incompatibility here.
Being a cynic, I always thought that this was just a ploy to make customers pay an upgrade charge to Oracle, rather than a real issue with AIX. It would not surprise me if it were perfectly possible for Oracle to have issued a patch for 8i, but this would have had little financial advantage for them.
IBM issued guidance that said that the kernel extension interface was changing, but this sounds very similar to the Adaptec driver issue mentioned. So no real difference from Solaris there.
The rest of the code may well have worked, but would have been completely unsupportable. IBM claimed in the AIX 5.1 readme that the only reason to recompile 64 bit code was to take advantage of the new features of the new release, which is not unreasonable.
Solaris' binary compatiblity was the Gold Standard
Sun went through so much pain with the Motorola to SPARC transition, and then even more so with the SunOS 4 BSD to Solaris 2 SVR4 transition, there was a "Never Again" declared within Sun's Solaris group. This is what led first to Sun's famous Solaris Application Guarantee, which was actually imitated (the sincerest form of flattery) by IBM a few years ago.
Solaris binary compatibility was so good even drivers worked across versions. Customers got so conditioned to things just working some were quite upset when they found their 32-bit Solaris 2.2 Adaptec SCSI card driver would not work with the 64-bit Solaris 7 kernel. That was a driver bit incompatibility, as the same driver worked fine if one booted the 32-bit Solaris 7 kernel.
IBM had a big problem when they went from the 64-bit version of AIX 4.3 to AIX 5.1. These two versions of AIX were completely incompatible, and it meant for example, you could not move your Oracle 8i database running on an p680 on AIX 4.3 over to a p690 on AIX 5.1 without also moving from Oracle 8i to Oracle 9i. That fiasco is what caused IBM to get its act together on compatibility.
IBM has cleared innovated tremendously in AIX over the last decade, but they have also copied madly from Sun. Those less transparent Solaris commands? Now available on AIX. Containers ... er, Workload Partitions? Now available on AIX. Branded Containers (i.e., Solaris 8 and Solaris 9 compatible containers in Solaris 10), now available on AIX.