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
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]
Many people in computing, we seem fixated on "percentages" when talking about CPU use - We need to fix that.
When a computer has an absolutely fixed number of CPUs on the time scale of a few years the percentages of the box makes a lot of sense.
But in a virtualised world we will have to change.
For 10 years, we can do Dynamic CPU changes to a LPAR (Virtual Machine).
Yesterdays 40% used is today's 80% because the admin guy added a couple of CPUs over night.
If we look at the percentages and see a... [More]
If while installing SUSE SLES 11.3 on your POWER8 machine from the regular DVD media, you get this on the console after 5 seconds after booting:
Welcome to SuSE Linux Enterprise 11!
Type "install" to start the YaST installer on this CD/DVD
Type "slp" to start the YaST install via network
Type "rescue" to start the rescue system on this CD/DVD
Welcome to yaboot version r22.8-r1190.SuSE... [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
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.
The people that join the AIX Virtual User Group are... [More]
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]
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]
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]
With day light savings time nearing, its a good time to check if your AIX version has the proper patches. There were some problems in some TL's last fall. The recommended levels are: AIX 6.1 Package Level shipped APAR/Filesets 6100 TL0 6100-00 IZ09600 bos.rte.libc 184.108.40.206 6100 TL1 6100-01 IZ22211 bos.rte.libc 220.127.116.11 AIX 5.3 Package Level shipped APAR/Filesets 5300 TL8 SP2 5300-08-02-0822 IZ22212 bos.rte.libc 18.104.22.168 Package Level shipped APAR/Filesets 5300 TL7 SP2 5300-07-02-0806 IZ11729 bos.rte.libc 22.214.171.124 If you have any questions, check... [More]
RSS is a web feed technology that allows you to monitor web sites that change frequently (blogs, technical forums, updates, news, etc). IBM has over 300 IBM RSS feeds which are listed on the following website. http://www.ibm.com/ibm/syndication/
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.
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]