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 part 2 of Systems Director licensing or at least working out what you are doing with System Director that requires a license. In part 1, we looked at listing (via the command line) the POWER machines that Systems Director was connected too. This time we what to find out the machines that Active Energy Manager (AEM) is controlling. Once you have installed AEM it is tempting to start monitoring and controlling all your Power Systems electrical use and temperatures but you should only use AEM if you have a license for AEM for each... [More]
When you install Linux on an IBM POWER processor machine (Red Hat, SUSE or now includes Fedora), you then need to add the IBM supplied additional RPM packages. These give you a whole bunch of useful tools like HMC comms so you can Dynamic LPAR change and LPM, diagnostic tools, and configuration listing commands. Plus more importantly nmon :-) The repository allows you to update your packages as new versions become available and to benefit from fixes and additional functions. Without these you don't get the full Power... [More]
In case, you did not notice (as its the silly summer season) AIX 7 is shipping in 19 days time. See the official AIX 7 Announcement Letter for all the details This is a whole 2 months early - well done guys.
March 11, 2007, marks the start of Daylight Savings Time this year. At 2 a.m. on Sunday, the time will officially "spring forward" one hour. Patches to HMC code have been available on the HMC home page: https://www14.software.ibm.com/webapp/set2/sas/f/hmc/home.html What happens if you haven't updated your HMC by the time DST begins? Will there be an impact on the managed serves? The HMC will not stop working, and neither will the managed servers. The time can be reset manually on the HMC. This will entail rebooting, but again, this has no... [More]
I use the following formula to size the minimum number of cores on replacement servers. The formula is based on "used" performance on the installed servers matching "used" performance on the replacement server. c2 = (u1)(c1)(p1) / (u2)(p2) Where c1 = # cores on the installed server p1 = "performance per core" of the installed server u1 = % utilization of the installed server c2 = # cores on the replacement server p2 = "performance per core" of the replacement server u2 = % utilization of the replacement server If consolidating multiple... [More]
I have tried to get permission to pass on these numbers publically but got no answer at all. As these are facts rather than opinions, I see no harm in them. So I will work on the old theory: "it is easier to ask for forgiveness than permission" ... here goes. The AIX Virtual User Group often asks a few questions as part of the registration process for the next webinar session and it generates fascinating statistics from real POWER and AIX users. Observations: The people that join the AIX Virtual User Group are well above the... [More]
Here is a great index page for AIX information. Most ofthe links are to www.ibm.com ... but you get to avoid theIBM search engine :-) One of the very nice features is that every link (or leastevery one I tried) opens a new window. http://www.aix.lap.hu There is also a Google-based search engine for AIX: http://www.aixsearch.com
Here is Jaqui Lynch's AIX 5.3 initial tuning guidelines for commercial workloads. Jaqui wrote and delivered the "AIX Performance Tuning" session at the "IBM System p, AIX, Linux Technical University" this year in Las Vegas. no -p -o rfc1323=1no -p -o sb_max=1310720no -p -o tcp_sendspace=262144no -p -o tcp_recvspace=262144no -p -o udp_sendspace=65536no -p -o udp_recvspace=655360nfso -p -o nfs_rfc1323=1nfso -p -o nfs_socketsize=60000nfso -p -o nfs_tcp_socketsize=600000vmo -p -o minperm%=5vmo -p -o minfree=960vmo -p -o maxfree=1088vmo -p -o... [More]
Starting in AIX 5.3 ML5, there is a new "topas -R" option that records theperformance of all partitions on a physical server. The command is runon just one server, and the output is stored in the /etc/perf directory. The "topasout" command converts the output file into a CSV or XML file. The CSV file can be imported into the nmon Analyser 3.2.3+. (Requires AIX 5.3 TL5 service pack 4 with APAR IY87993) The advantage is that topas is a supported tool. The disadvantage isthat it is not well documented, and you have to do some of the parsing. ... [More]
HACMP recently announced support for the following: HACMP 5.4.1 for Linux HACMP Support Announcement for the JS22 HACMP supports the IBM 4-Port Ethernet 10/100/1000 Base-TX PCI-X Adapter HACMP announces support for P6 p520 and p550 HACMP supports IBM VIO Server V1.5 Click on the above linked text for full support details.
Configuring a Shared Ethernet Adapter (SEA) for failover in the Virtual I/O Server V1.2 is much different than in the original version. Because the code just came out last fall, it probably hasnt been implemented yet in many shops, but it will be. The pSeries ATS group in Dallas has done some testing and we thought we discovered a potential gotcha. Turns out, we didn't, but it did lead to some interesting observations. Until now, most documentation shows putting the Virtual I/O server's IP address on the SEA. The Virtual I/O server should... [More]
The following paper by Ralf Schmidt-Dannert discusses the performance impact of AIX micropartition options on a 2 tier Java/C++/Oracle application. His benchmarks show micropartitioningcan have a positive impact on application performance. His conclusionsinclude: 1. The micropartition CPU sharing improved performance over static LPARs2. SMT improved performance (default AIX setting)3. Don't over configure Virtual Processors (My recommendation is to configure at most one Virtual Processor per CPU in the free pool)... [More]
The System p Support site has migrated to a new subscription service tool for support notifications named My notifications You'll need an IBM Developerwork's ID. (It's free and painless to register a new ID) Subscriptions for IBM Systems provides the following new features: - Ability to create multiple subscriptions with different topics and notification options- Ability to create and name multiple folders to organize your subscriptions- Ability to specify weekly or daily notifications when a topic is updated- Ability to access the PTF Cover... [More]
One way to determine if there is an I/O bottleneck in AIX's Logical Volume Manager (LVM) layer is to run the "filemon" command. The filemon output shows I/O response times for both Logical Volume (LV) and Physical Volume (PV) layers. If the difference is over 2-3 ms, there could be an I/O bottleneck in LVM. If so, check the LVM buffer statistics at peak I/O loads. Run the "vmstat -v" several times, and look for increasing "I/Os blocked" in any of the buffers. (The rate of change is important, not absolute values). Use the "ioo" command to... [More]