AIXpert Blog is about the AIX operating system from IBM running on POWER based machines called Power Systems and software related to it like IBM Systems Director, PowerVM for virtualisation and PowerSC for security plus performance monitoring and nmon
This is a follow on from yesterdays blog due to Chris Gibson highlighting a question/concern from one of his customers in Australia.They were comparing Power6 and Power7 and the utilisation numbers from the SMT Logical Processors and the graphs look different. I looked at some nmon data (what else!) and yes they are looking different and then I ran a simple generated workload test and duplicated the graphs. Below I then explain them - once again these are my personal observations rather than an official AIX developers insider statement. I... [More]
This week I spent 4 hours with a customer covering many advanced WPAR topics and took way a bunch of questions that I had to check the answers and ask the WPAR developers themselves to be sure I had the right answers. If the questions were not clear to my customers and I did know initially know the answers then there may be others with similar issues so I thought I would share the answers with everyone. 1) Workload Partitions - What is the road map? Well, I am not going to make announcements on a blog for sure. If you are new to WPAR, I can... [More]
IBM is enhancing the AIX release and service strategy
effective February 15, 2011.
The key changes are: Three years of new fix support for
each AIX Technology Level update (starting with AIX TL 6) One Technology Level update per AIX
version per year (planned for the second half of the year) Service Packs for Technology
Levels will be released about four times per year
These changes reflect client requests for IBM to provide new
fix support for individual Technology Level updates for a longer period. The
intent is to reduce... [More]
I get email a few times a week like "Nigel, what do you recommend for getting a good view of what the whole Power Server is doing, what resources are free for reuse for further Virtual Machines and which Virtual Machines are busy" My detailed thoughts are on the DeveloperWorks AIX wiki here: AIX Other Performance Tools but it appears no one reads websites any more, so I thought I would blog a few examples by screen capture to illuminate what is available. My first Whole Power Server and Virtual Server view recommendation is Systems... [More]
Hi, I just release a fifth hands-on movie this month and on this interesting topic. You can find the movie here: Shared Storage Pools 2 - Thin provisioning, monitoring free space + Alerts Shared Storage Pool Thin provisioning is pretty cool and saves a lot of disk space . Effectively the 100's of GBs of unused disks space in 100's of Virtual Machines (LPARs) are bought together in one place in the Shared Storage Pool and then can be used for real. All this without the use of clever disk subsystems. The risk is that you use all the disk... [More]
The title should read "Local, Near & Far ..." - I will not correct it or links might fail. With a shared processor virtual machine (I am calling this "VM" but was called LPAR!) there are various suggestions of setting Entitlement ("Desired processing units" on the LPAR profile on the HMC, I am calling this "E") and Virtual Processor numbers (I am calling this "VP"). For Capped, the Entitlement is the maximum guaranteed CPU time that you can't go over and you round up the Entitlement to the... [More]
With AIX 7 and POWER7, you now have the option to run the old withdrawn AIX version 5.2 within a
WPAR with this new offering - AIX 5.3 Workload Partitions for AIX 7, version 1.1 This will run the same AIX 5.2 OS, same middle-ware and same application
but on right-up-to-date hardware and OS. Then you can remove the old
POWER4 (or older hardware) to: Reduce electricity & heat, Free up floor
or rack space, Reduce hardware maintenance or if you don't have it, reduce your risks, Plus either a
performance boost due to POWER7 or reduced... [More]
I am working with a larger Power 7 customer and learning lots about life in the large and professional computer room. Oh Gosh!!! My Power Virtual Machine (Logical Partition) is totally busy. Oh Heck!!! Look at all that System time, we have a serious problem!! Or do we? Take a look at the below nmon stats and make up your own mind before scrolling down. Actually, we are in offices many miles away from most of the Power 7 computers because the machines are
split across three sites. More than twenty Power 7 Model 795's is
enough to... [More]
VIO is a specialized Power5/Power5+ partition that allows clients to sharedisks and network adapters. This IBM Redpaper provides best practices for planning, installing, maintaining, and operating the VIO partition. http://www.redbooks.ibm.com/abstracts/redp4194.html?Open This Redpaper begins where the Advanced POWER Virtualization Redbookleaves off by adding best practices based on real life experiences. http://www.redbooks.ibm.com/abstracts/sg247940.html?Open
IBM announced lots of Power Systems software yesterday but the official announcements are pretty thin on the details. I have many Twitter tweets asking "What the heck does that all really mean?" and the official statements are marketing messages and not technical information like:
How do you get that working?
What are the pre-reqs?
What are the actual commands?
What does the Graphical User Interface look like?
How does that help me as a System Admin person?
Yes, I admit it I am a "hacker" in the old sense of the word i.e. Definition 4 = A person who is good at programming quickly.See Hackers Dictionary below. I was think that there are certain books every one in the computer industry should have read before they can claim any level of computer expertise. If you have not read them don't tell any one and quickly get yourself a copy and read it quickly. Thumbnails are borrowed from Amazon - thanks guys and good to see all these important books are still available. My five top books all... [More]
Here's a new Redbook that provides a system administrator view of the technical differences and methods necessary to complete a successful migration from Solaris to AIX 5L based systems. It also appears to be a good general AIX admin reference. Solaris to AIX Migration: A Guide for System Administrators http://www.redbooks.ibm.com/abstracts/sg247245.html Other Redbooks in this category include AIX Reference for Solaris Administrators http://www.redbooks.ibm.com/abstracts/sg246584.html?Open AIX 5L Reference for HP-UX System Administrators... [More]
In the past, a high wait I/O was a good predictor of a bottleneck. However, today it's a bit more complicated. High wait I/O may not imply an I/O bottleneck. You'll have to consider other factors, which I'll list below. The reason high wait I/O may not be a good predictor is because CPU performance has significantly outpaced disk performance. Here's a situation I ran into that illustrates the point. A customer replaced an older server with a new pSeries server. The new server had 6x the CPU performance. They used the same SAN for disk... [More]
Just came across this good AIX wiki article about monitoring the POWER7 CPU/core frequency changing on the fly and the new lparstat command options ( -Ew). This allows you to see what is happening with your GHz (like pmcycles -M but collected regularly). This article is written by a guru in the AIX Performance Tools developers group. It explains how the utilisation numbers are adjusted to allow for GHz using the PURR and SPURR hardware counters built in the processor to get accurate CPU stats. Check it out here - CPU Frequency Monitoring using... [More]
For Systems Director 6.2 supports Firefox 3.6, 3.5 and 3.0 - you have to be nuts to not be using 3.6 IMHO! Internet Explorer 7 or 8. See http://publib.boulder.ibm.com/infocenter/director/v6r2x/index.jsp?topic=/com.ibm.director.plan.helps.doc/fqm0_r_supported_web_browsers.html Unofficially, I find Google Chrome 12 works fine too. For Hardware Management Console (HMC) (I am assuming a recent HMC V7R7.3 level here) it supports (from the Power7 manuals) Internet Explorer 7 but says IE 8 is not supported - just tried this and the left hand menu got... [More]
After you have started and used your virtual machine (VM) for a while, you may decide to change its size using a Dynamic LPAR (DLPAR) change from the HMC (or SDMC or IVM, of course). This has virtual machine placement implications. When shrinking your VM, the hypervisor will decide which CPU or memory (LBM) to release and it might not select what you think is the obvious choice. When enlarging your VM, we might thing there is an obvious way to grow in a balanced way but we can't see: 1) where physically our virtual machine is placed in the... [More]
Here is another question from that larger Power 7 machine customer. They have large Virtual Machines (Logical Partitions) and can't see all the CPUs on the screen. This is made worst by Power 7 machines - not a problem with the processors or machines but there are: So many CPUs on larger machines like Power 770/780 and the mighty Power 795 Then the new Simultaneous Multi-Threading (SMT) now means four threads per physical CPU (core). This means lots of physical CPUs and each has four logical CPUs. So what happens on the screen - you see a... [More]
As of Service Pack 1 of HMC V7R3.3, there's a new access control that must be considered when creating new users. By default, remote access is not allowed, even if in general you've already allowed remote users. The box to check if you want to allow remote access is found under User Properties in the task used to create or modify a user's account. When creating a user account, remember to click on User Properties at the bottom of the task menu. In the lower left corner of the menu that comes up next you'll find a check box that says Allow... [More]
POWER Relative Performance (rPerf) is often used as a way to approximate the expected difference in performance between two Power Systems servers. Although rPerf is a useful tool, it is important to understand the limitations of using rPerf to provide an estimate the performance of your specific workloads in your particular environment with a new server, First, rPerf numbers, like any published benchmark, represent the best case result when the application, configuration and system resources are all optimized -- factors that are likely not... [More]
So I got asked, just as an example configuration which forces lots of workload per CPU: Given a 16 CPU POWER machine and a need to run 100 workloads, would I recommend 100 LPARs or 100 WPARs? In case you are not familiar with POWER technology: LPAR = Logical Partition used the PowerVM to split CPU, memory and I/O across multiple virtual machines (also called virtual servers). The I/O is handles by a special purpose LPAR called the Virtual I/O Server, which provides virtual network, virtual disks, virtual optical and virtual tape. Each LPAR has... [More]
I HAVE UPDATED THIS BLOG WITH BETTER, UP TO DATE AND CORRECTED INFORMATION FROM THE DEVELOPERS Read the comments for lots of useful information - Thanks Guys for the corrections WARNING: Advance Technology Support (ATS) Europe is getting reports today from users and IBMers that the POWER7 firmware 770 level as a pre-req check missing! could be much better . This results in the HMC agreeing to upgrade your POWER7 or POWER7+ machine to firmware level 770, when it is not supported and does not work. This causes very bad problems: On smaller... [More]
Hi, I am preparing for a Power Systems Technical University in Las Vegas, USA and Lyon, France in October. I have a session with the title below and I am seeking feedback from technology guru's like yourselves. Which four of the below ten technologies do you think are "most likely to be normal in five years time"? Please comment on this AIXpert (see "Add a Comment" below) with your four top technologies. I will post the overall results as a graph in roughly two weeks time. Below here there should be a large image of the ten... [More]
We all tend to concentrate on the CPU first and the memory second. CPUs, as the "brains" of the machine, does get a high focus and have a lot of extreme technology within it but the RAM is the "guts" of the machine to "feed" the CPU with nutrient data. OK, let us stop the analogy there :-) Along with reducing the number of CPUs via a lower virtual processor count, we also need to have the CPUs matching the memory - so AIX has a fighting change to localise a running process to its home SRAD and thus have it's data... [More]
Just completed the move of the POWER and AIX Hands-on Movies to YouTube videos - after pruning we have 97 of them. This means you can watch them on your mobile Smartphone and Tablets in addition to your workstation/personal computer. You can find them all here:
YouTube look for my "Nigel Griffiths" Channel http://www.youtube.com/user/nigelargriffiths This should mean they are simpler to find, search for and view. During the transfer I pruned out a few of the older ones particular Systems 6.2 as we now have a set of Systems... [More]
I asked Scott about a Redbook for the new VIOS functions for Shared Storage Pools and he told me that chapters had already been added to the current PowerVM Redbooks. I almost fell of the chair! I have been ignoring the regular Redbook update emails - but I guess I should pay more attention. So I took a look and found the Shared Storage Pools have chapters in two regular PowerVM Redbooks - note you have to download the most recent updates. IBM PowerVM Virtualization - Introduction and Configuration SG24-7940 IBM PowerVM Virtualization -... [More]
Your first reaction might be "Why would you do that, Nigel?" and "Isn't this a AIX blog: Why are we talking about Linux?"
Well AIX is great and all that but when it comes to Open Source it is not Linux. Like it or not most Open Source stuff is developed on Linux and there are readily available binary compiled for Linux and 100's of Open Source packages actually come with the the distribution on their DVD media and arch repositories on the Internet for rapid and straight forward install and updates.
Many countries switch to Daylight Saving Time (DST) next weekend March 25th - unfortunately you may need to apply a fix to AIX 6 and AIX 7 before the change or programs can get inconsistent time from various time function and systems calls. This could have a major impact on many tools, for example, make, logs and databases ... well just about anything that uses a time value. There was an earlier temporary fix available but now there is a fully details final fix. Please got to the bellow website for all the details :... [More]
So you have Discovered, given Access and run Inventory on your HMC and it is not finding the Servers and Virtual Servers that the HMC is connected too! What do you do next? Well here are a series of suggestions for you to try (this is not an official diagnostics path but might help you out): How much memory has your HMC got? I get people trying to use old HMCs and the original ones had just 1 GB of memory. This is basically not enough these days - in my humble opinion - unless you have just one machine! But how do you find out what you have?... [More]
In case you missed the announcements, I have released four new movies this week: Shared Storage Pools phase 2 - Getting Started - movie 101 Active Memory Deduplication Theory - movie 102 Active System Optimizer - movie 103 System Director 6.3 First Use - movie 104 Catch them all at the home of POWER6, POWER7, PowerVM, Systems Director and AIX Movies - or save this link for 21 hours of intensive techie learning - http://tinyurl.com/AIXmovies ps: The previous movie last month about installing Systems Director 6.3 on AIX is a good movie... [More]
I've just told me this is now available from http://www.ibm.com/systems/support/tools/systemplanningtool/ Update to Version 4.10.323.0 (once you have 4.09.323 installed) OK, we have waited long enough so "hurray" its here at last. My colleague in Norway is going to use this to install a very large Power 795 in Norway next week. He is so happy because its going to save him hours and hours in setup time and will get it right first time.