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Dynamic Logical Partitioning for Linux on POWER
An anonymous reader writes "Logical partitioning provides POWER processor-based servers with the capability to do server consolidation and optimize system resources. Dynamic logical partitioning enhances this capability by providing control of the allocation of the resources without impacting the logical partitions availability. Linux on POWER supports dynamic LPAR for changes to physical I/O, virtual I/O, and processor resources."
This has been available from IBM for years. I've only started with POWER 4 but I think it was available a few versions back as well with limited functionality on Linux. The more advanced features recently came available with the release of the POWER 5 processor. Nearly all of the RAS features are now available for Linux on IBM that have been available for AIX.
They also support Redhat and SuSE. Good stuff!
And for once I drool over something I have only vaguely an idea of what it does.
What it does is allow reconfiguration of system resources, such as IO cards, memory or cpu's (or on Power 5 with AIX 5.3, portions of a cpu), etc. on the fly without having to reboot your server to acknowledge them. AIX has had this capability since 5.2.
It's great for being able to juggle your resources on the fly, but it really comes in handy for moving your DVD drive between partitions on a frame without having to reboot. Having to reboot 2 servers just for that is a royal PITA.
Simultaneous Multi Threading is an even cooler feature of the POWER 5 chip!
Here's a pdf.
In the future, I would want to not be isolated from my friends in the Space Station.
Nice write up from IBM, but it's important to remember thaat the Linux kernel only supports dynamic changes in CPU and PCI devices, you can't move memory around. AIX allows dynamic memory; the Linux kernel will need some fundamental chages to enable this. Power5 is indeed the coolest technology around today, but Dynamic LPAR started on the Power4 back in 2001, so this is kinda old news.
-The Mad Duke
The POWER series has this on-chip, so it's a whole lot faster than doing it via software and it doesn't require a reboot. The dynamic partitioning is the real difference between the POWER series and the PowerPC chips IBM sold to Apple. This is a feature carried over from IBM's mainframe days, and if you actually need it, it is very cool.