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
I have just upgraded my EMEA Power Systems Advanced Technical Support internal Wiki Apache Web-server to the very latest AIX level, which is AIX 6.1 Technology Level 6 Service Pack 5 or AIX6.1TL6sp5 for short! Then I noticed that the nmon at this AIX level has been updated - I worked the code for the internal prototype of this new feature some time ago and it has arrived in the official topas/nmon code at this release - C O O L . The latest release AIX 7.1 service pack has this new options too. The problem: As the numbers of CPU goes up with... [More]
The title should read "Local, Near & Far ..." - I will not correct it or links might fail. In this entry we carry on from part 5 but we are going to look at setting the virtual processor number for the virtual machine . There is a side effect that is not obvious and after 6 years of using them, it never occurred to me so perhaps it is news to others too. The problem of virtual processors is that they are ephemeral - i.e. they don't actually exist and costs nothing. So I find most systems administrators feel they can be generous... [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.
The official rPerf rating (relative performance rating of Power based machines) are available in the pSeries, System p and now Power Systems "Facts and Features" documents that are on the IBM website. It is best to use Google for them (searching for "pseries Facts and Features" works for me). You may want to know the rPerf rating for your LPAR and an LPAR that is not one of the officially rated numbers of CPUs/Cores. There may be ratings for 8 and 16 CPUs but your LPAR has 13 CPUs! Well, you can run the rperf script on the... [More]
*** STOP PRESS *** - See the update in red at the bottom.
I was asked this lots of times at the recent POWER Technical Universities in Orlando and Athens.
Compared to a low numbers of local disks
The LUNs on a SAN disk subsystem with caching are very fast - even a simple test like AIX install times have halved. In addition, you don't have to fiddle about with stripping AIX Logical Volumes across disks or retro fit this to rootvg Volume Group filesystems after the install.
Compared to a... [More]
I am using the VIOS Shared Storage Pools more these days and it reduces my system admin time and I really like the Thin Provisioning feature as I have limited SAN disks. Any way, I dusted off an machine that I did my initial investigation on and decided to rebuilt the cluster (of one VIOS) now that I know what I am doing :-) The command : cluster -create -clustername galaxy -repopvs hdisk2 -spname atlantic -sppvs hdisk3 hdisk4 hdisk5 -hostname diamondvios1 fails with "PV IS IN USE hdisk4". PV meaning Physical Volume. Yes,... [More]
Installing Open Source on AIX systems can be a little .... um .... frustrating and I have just been round that loop with installing Ganglia the excellent Performance Monitoring tool to demonstrate it and actually use it too on my own servers. The hard bit is that for every Open Source program, that you want to install, there is 10 to 20 prerequisite packages that you need to install first and you go round this the loop four times as the prerequisites have prerequisites .... This has got known as the "RPM dependencies form... [More]
LPAR2RRD Briefly, Based on the same HMC data that Systems Director gathers is LPAR2RRD but it saves the data in the famous and excellent rrdtool database and graphing tools. This is a supported by the developer which is Pavel Hampl, IBM Czech republic, as a personal project tool and does a very good job. For more details and a sample website to look round see - AIX Wiki page for LPAR2RRD I note this is a sourceforge.net project now - See the above for a link to the project and code Cut from that AIX wiki page for the project here (all... [More]
I thought I should summarise the long eleven part Local, Near & Far POWER7 Affinity series. 1) Placement: Find out the layout of your boxes CPU and RAM and if the RAM is evenly distributed across available DIMMs Find out the placement of your Virtual Machines (LPARs) with lssrad -av - or - topas -M 2) SMT4 : Expect POWER7 SMT4 CPU use to “look” different POWER5 & 6 have two equal threads POWER7 shuts down threads 3 & 4 and even thread 2 - when there is not enough processes running. 3) Entitlement : Only set minimum Entitlements,... [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]
I have been looking at some nmon data from an IBMer looking into a customers machine. The virtual machine (LPAR) is running the Oracle RDBMS with 75 dedicated CPUs - on a POWER7 Power 795 at 4 GHz.
The Excel spreadsheet is quite scary at 144 MB thank goodness my Thinkpad has a SSD but not the record by a long way. Too many data save points can ready add u and so too can lots of processes if you are saving process data. Also with 75 CPU and SMT=4 that is 300 Tabs for Logical CPU, 300 for PCPU and 300 for SCPU and that... [More]
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?
Finally, I found the time to try this new exciting feature and it was really simple to create and operate. I captured movie footage of my first attempt and it all worked (once I removed my spelling mistakes in commands). It only took two commands. So the technology has advanced concepts but it really easy to use, COOL! Some of the commands come with long option names like "-custername". A quick misquote from Star-Trek, never goes wrong: "It is UNIX Jim, but not as we know it!" One command to create my cluster,... [More]
AIX or VIOS Start-up Memory Problems I have been working with a couple of customers that have a newly setup AIX Logical Partition (LPAR) that fails to start due to not having enough memory. The common factor is that the LPAR for AIX (or VIOS) includes a good number of what I call "high speed" adapters like 10 Gbps Ethernet, or 4 Gbps or 8 Gbps Fibre Channel adapters. They tend to have multiple adapters of each type for redundancy and throughput. For example, trying to start the LPAR with 1 or 2 GB of memory but it turned out they need... [More]
The below URL takes you to the top of the Systems Director 6.3 online documentation http://publib.boulder.ibm.com/infocenter/director/pubs/topic/com.ibm.director.main.helps.doc/fqm0_main.html As a rule I use Firefox 3.6.24 all the time for my browsing as it works well for Systems Director and Hardware Management Console (HMC). Later Firefox versions have "variable" results which re frustrating and that just slow me down. The Firefox developer when mad and got to version 8 suddenly over what appeared to be a few weeks but have realised... [More]