Edit: Did you ever do much with WPARs? The links to Nigel’s articles no longer work. The AIX 7 IBM article no longer works.
Originally posted July 6, 2010 on AIXchange
So far, adoption of WPARs has been slow. Customers like the workload isolation and resource flexibility they get with LPARs, so they’re less interested in the WPAR story. In fact I often hear customers tell me they’re happy to get away from the whole WPAR/container concept and get into micropartitioning and LPARs on Power Systems.
IBMer Nigel Griffiths gives some food for thought as to why we should get on board with WPARs. I’ll summarize his arguments:
1. LPARs take only minutes to create, but creating WPARs takes just seconds.
2. LPAR requires 512 MB to 1GB to boot AIX. With WPAR, you need fewer than 60 MB (yes, I said megabytes).
3. You can share application code — say, 1 GB — in each and every LPAR (40 LPAR = 40 GB). Or you can share just read-only copy for all WPARs (40 WPAR = 1 GB).This not only requires less maintenance, it saves disk space and memory. (If the application is loaded in the Global AIX then there’s only one copy in RAM.)
4. Maintaining one Global AIX via the SYNCWPAR command is much easier than updating, say, 40 copies of AIX.
5. Application mobility is much simpler to organize than LPM.
6. The Global AIX administration can see and change all WPAR filesystems — e.g., adding a tool to /usr/local/bin can be done by simply issuing the cp command.
7. Rapid cloning is easy and allows you to use “disposable” images that can be created, tinkered with and readily discarded.
8. If you mess up a WPAR, you can fix it via the Global AIX. If you mess up an LPAR, your system may not boot!
9. Backups are much easier and smaller than a LPAR mksysb. A default WPAR backup file is around 75 MB. Of course it’s more if you have applications plus data, but you still don’t need 2 GB of data as you do with an LPAR backup.
I have left out a few of his points — Nigel’s original entry has 12 items — so be sure to check out his full list.
Nigel has another article that covers a couple of new AIX 7 features, one of which is the capability to run AIX 5.2 within workload partitions:
“We all know running AIX 5.2 is pretty dumb (as it’s not under normal support), but it happens. For some reason the code can’t get updated, the ‘if it ain’t broken don’t fix it’ rule sticks for so long that it becomes a nightmare to update or it’s just not worth the manpower to upgrade a small application. But this also tends to mean it’s on hardware than is costly to maintain, actually large foot print given is lowly computing power, energy hungry, little or no virtualization. So picking up that AIX image (mksysb) and putting it in a AIX Workload partition is such a cool idea. It is then running on a much faster POWER7 machine, lower maintenance, sharing resources in virtualization, less energy use and freeing up computer room floor space. It’s win-win-win-win — and you then get AIX5.2 support (OK somewhat limited support as it’s been functionally stable for many years).”
For more general looks at IBM AIX 7, here’s Ken Milberg’s introduction that appears in the IBM Systems Magazine June 2010 issue. And here’s an official AIX 7 preview from IBM.
Finally, here’s my brief preview that I wrote in April.
What have you been reading about regarding AIX 7? Please share your links by posting in Comments.