Please provide comments on this blog entry - I want to know where I have it wrong?

With IBM's massive investment in Linux on Power my brain hurts trying to express the advantages.  This is because the technology is excellent but the bits you want depend on where you are coming from.  So I have tried to break out potential users in to various types.

For the record I am an Ab Linux on POWER User type!

A - Current AIX and POWER user

Already understands the POWER infrastructure, AIX and/or IBM i and are adding a new operating system (Linux) to the mix.  They can install a HMC and VIOS in their sleep.  As AIX is UNIX and Linux is a UNIX like operating system - loads of AIX admin skills will transfer. You will miss AIX's smitty, LVM for disk management and JFS2 file system. Linux on a POWER server does not normally have a graphics screen so you miss out on that lovely Linux "eye candy".  SUSE has Yast (smitty) but the variety of disk management options and file systems will be confusing to understand at first.  As you know VIOS well running Linux with virtual disks (particularly SSP4 mode) can avoid some Linux disk management complication.

Why if you are happily running AIX why would you start using Linux?

1. Most open source packages are a 2 second install from the OS media for Linux and it is completely up to date and compiled for your specific OS release. *** FLAME SUIT ON ***
   This is much simpler than with AIX running open source.  There I have said it - sorry AIX guys but that is my experience.
   *** FLAME SUIT OFF ***
2. Some of the "new wave" applications are based on Linux like Watson's Hadoop and Big Data Analytics.
3. When you boil it all down you find the cost of AIX and Enterprise Linux are similar so that is no massive issue - both can be purchased from IBM if you prefer "one stop support".
4. There are also free Linux versions but with only Internet support (Google is you friend) - that will do nicely for some proto-type or system admin work or non-production class workloads. No need to force your way through the purchasing process - remember I work at IBM I know your pain!  Debian and Fedora are available now and there is another in the pipeline for POWER8 - can't say more at the moment.
5. You may keep mission critical workloads on AIX with deeper integration into the hardware but there are many other workloads that suit Linux's currency and ease of use.

I think there are different groups using more Linux on Power all the time for different reasons:

• a - The"AIX or dead" team

1. Pure guess work here but this team's gut reaction is to find 100 reasons why Linux can't happen - dare I say some reluctance to even think about it as it might involve... work!
2. They may start off saying Linux will cost money QED: no chance buddy!  See above for the answer to that (~same as AIX or free).
3. Then claim Linux has features missing that they absolutely must have but really need to work through the Linux equivalent and if using Linux for non-critical production then do they really need the all these security, backup, monitoring, printing, alerting, .... applications to run an internal wiki website?
4. *** FLAME SUIT ON ***
   Linux out of the box is a bit more secure than AIX!
   *** FLAME SUIT OFF ***
5. Think telnet and ftp are working as default on AIX - if either of these are available you have no security - on AIX they need to be switched off - the aixpert command does this in a second or two and a further 100 AIX hardening rules but that is available under Linux now (with a different name).
6. It is also well reported that many people have dual standards:
   • If its AIX it must have: HACMP, fully redundancy, cold or warm stand-by hardware and a half dozen packages for security and all fixes have to be pre-tested before applying to production (resulting in AIX being back level an less secure in some cases)
   • If it is Linux it does not necessarily need all these and a policy to upgrade the Linux OS soon after the fixes are available.
7. I am not saying one is right and one wrong but some thought and flexibly is needed rather than rigid old rules to avoid work.  The alternative results in "missing the Linux trick" in a King Canute posture.

• b - AIX at heart but I can do Linux too

  1. Doing some Linux seen as a way to stop/slow down all these tiny Intel boxes sprawling across the machine room with many not being setup in a rush and not using enterprise methods - you know it is creating a man-power problem for the future.
  2. Running Linux can also soaking up some spare capacity in the POWER estate - it is doing some server consolidation before you create the problem in the first place - so its practically free computer resources and given Power machines with PowerVM can be driven harder will have little effect on current workloads.
  3. These guys will start with wanting to know the Total Cost of Ownership (TCO) but then go for a "sweat the assets" or "harvest what we have already" story.
  4. Once we have experience and working examples we can offer to reduce the costs of new Linux virtual machines and raise the standards to enterprise class AND shared resources between AIX, IBM i and Linux workloads for optimisation reasons.
  5. I hope my manager does not read this next bit, there is also the fun!  I get paid to "play"/research Linux on company time. Life is sweet!

• c - Big Iron Giants

  1. This team have the mighty Power 770, Power780 or Power 795 machines with Capacity Upgrade on Demand (CUoD) - which means the machines have unactivated CPU and memory resources in the machines already to be activated and used.  CUoD is an optional feature which you should know if you have it. These resources can be switched on temporarily for a fee or permanently at a price. It is used so that in a high transaction load period (like Xmas in the retail business)  the extra CPU/memory can be added very quickly (in IBM terms :-) and with zero interruption to the workloads and the new resources added to the virtual machines on the fly. By the way - IBM calls these Dark CPUs and Dark Memory - they are in POWER users machines but logically switched off and IBM would like users to switch them on.
  2. IBM is offering the Integrated Facilities for Linux (IFL) which offers a package of 4 cores and 32 GB of memory at a special low price if you prove you are only running Linux on these cores/RAM - that can be done pretty simply using PowerVM features on the HMC (which is mandatory on these large machines).
  3. If you have Dark CPU/RAM - "please ask your IBM or Business Partner rep." for the IFL price - you might be shocked (because it is low).
  4. If you were thinking of doing more Linux on Power on these larger machines then the price just dropped significantly.

B - Current Linux on x86 user

You will know the Linux OS well and how to run it native or under virtualisation systems like VMWare, KVM, Virtual box - also know the virtualisation concepts well.  However, a HMC or VIOS is a bit of a mystery and they will seem a pretty complex virtualisation system - with many fine tuning controls and new terminology. I don't know lots of Linux on x86 people and how they view PowerVM, so feel free to correct my bad thinking here!

I think there are different Linux groups thinking about POWER for different reasons:

• d - Needing POWER's higher scale up

1. With Power Systems mid-range from 64 to 128 CPU cores and the top-end going to 256 CPU cores there are some Linux application that will scale better on these large SMP machines than on smaller Intel machine. Sure there are some large Intel machines too but with lots of eggs in one basket the POWER RAS is a serious benefit.
2. You can shoot me down if you like but Oracle RAC on four 16 way machines is not going to match a non-RAC 64 way single instance.  We know this because: why else would Power have many 256 CPU core Oracle databases running today?
3. There is also the SMP maths were a larger machine with virtual machines can be driven to higher utilisations levels before performance dips. Multiple islands of computer power with some red hot and suffering and lots other machines largely idle is a recipe for performacne issues and not sweating assets.

• e - Interested in some POWER specific features

1. That feature might be the high numbers of CPU core or 16 TB of RAM or it might be the extremely fast memory bandwidth due to the numbers of memory controllers and dozens of buses or the Acceleration features like Decimal Floating Point (DFP) of the memory compression or the  in core engine or the Active Memory Sharing or the mixed physical and virtual adapters in a virtual machine with Dynamic LPAR operations or the native ultra high speed Ethernet adapters for super low latency or having literally 100's of adapter slots or the   ... and the list goes on and on.
2. IBM is running loads or prototype proof of concepts and benchmarks for Linux applications wanting a "piece of the POWER action" based on these advanced features.

• f - Interested in an easier way of life

1. It is easy for "old guys" like me to become all too familiar with excellent POWER technology that was have taken for granted as it appeared a couple of years ago and we think it is normal and take it for granted every computer has these advanced features.
2. Even simple things like a HMC to remotely start/stop the VM and whole machine, install firmware and also report back Reliability (RAS) problems before they cause an outage and get a Customer Engineer on their way with a spare part. Is this normal in a white box Intel server?
3. I was reminded of this by a YouTube video from friends at the IBM Montpellier Centre in France - Boost your Linux with IBM Power - 6 minutes as they reminded me of many of the POWER features that 5 years ago we highlighted for UNIX users and now apply to Linux users.
4. When I have a new POWER machine arrive in the computer room, we lift it into the rack, plug in the HMC, Ethernet, SAN and mains power and go home - I do everything else from 50 miles away.  Yesterday, I tried to do a fresh install of a Intel machine with Linux - It has some RAID controller I don't understand but could live with the setup but then it refused to boot off DVD - I will drive into work next week to try again.

• g - The "Linux or die" team willing to try POWER - If it is exactly like x86

1. Now IBM can match the TCO for Linux on x86 with the PowerLinux machine range, we can interest the Linux on x86 gurus that have all their install, roll-out and preferred setup working just fine "thanks you very much" including virtualisation under KVM.
2. This is where the PowerKVM product will be very useful - it is to be released soon but already talked about at Linux conferences by IBM top brass. This will look and feel like a x86 machine running Linux KVM (because that is what it is) but with the POWER features too. So you boot the PowerLinux machine in KVM mode and run your SUSE or Red Hat under KVM and it looks and operates the same way.
3. No up hill struggle for Linux KVM team learning all the details of IBM's HMC or VIOS.
4. There is also some exciting new modes and features for running Linux on POWER on the future POWER8 PowerLinux machines -  I wish I could say more but I love my job and so I can't leak information.  I was gob-smacked when I was learnt what the IBM Linux kernel guys are up to! - I will blog when I am allowed.

Well - I might have annoyed most Linux and AIX gurus with my comments - I warmly invite lots of comments - I want to learn more from your hard one hands-on experience.

In my next blog I will be look at the 28 dozen different ways of installing and running Linux on Power - Yes, that is a bit of an exaggeration but there are loads!

The End