Linux on IBM Z and LinuxONE - Group home

Inside the LinuxONE III


As a technologist and self-proclaimed datacenter geek, one of the things I was most excited about upon joining the IBM Z team was getting familiar with the hardware. One of my first missions was seeking out hardware diagrams so I could learn about the internals of the LinuxONE Rockhopper II and Emperor II. Back in July when I was visiting the IBM offices in Poughkeepsie, NY for the first time I made sure to set aside time to visit the client center where IBM z14 and LinuxONE machines were on display and running.

On September 12th the exciting news came out that a new version of the hardware had been released: z15 and LinuxONE III!

On the hardware side, the first thing you may notice is this new machine fits into the space of traditional 19" racks. To allow for the maximum amount of flexibility, a configuration can then be built that has from 1 to 4 frames, thus taking up 1 to 4 spaces in a datacenter designed for 19" racks.

1-Frame Linuxone III

4-Frame Linuxone III

When you open up the front covers you'll mostly see fans, regardless of whether you go with radiator or water cooling option.

3-Frame Radiator Cooled

4-Frame Water Cooled BPA (Bulk Power Assemblies)

The rear of these machines is where things really get interesting as you can see all the components.

4-Frame Radiator Cooling and iPDU Power

4-Frame: Rear Water Cooled with BPA

Memory options range from as low as 8TB in a single frame, up to 40TB if you do a four frame system. In the realm of processors, the new LinuxONE III has a range of 1-190 cores. Depending on the number of frames, the following table shows the options based on the number of drawers and frames in your configuration:

CPC Drawer Customer PUs Max Memory Frames
5 190 40 TB 2-4
4 145 32 TB 2-4
3 108 24 TB 1-4
2 71 16 TB 1-3
1 34 8 TB 1-3

The processors are 5.2ghz each, with:

  • Enhanced performance with new on-chip compression
  • Four levels of cache (to help avoid untimely swaps and memory waits)

Angled CP with Dime for Scale

Once you start looking at actually putting workloads on your system, you can have up to 85 LPARs per system.

Additional specs include up to 22 dedicated I/O offload processors (SAPs) pre-allocated per system and the ability to connect up to 60 PCIe control units across up to 12 PCIe I/O drawers in a 4-rack system.

I'm really thrilled about the flexibility of these configurations. The ability to choose 1, 2, 3, or 4 rack systems based on your computing needs and space is quite the revolutionary feature with these new models. I’m looking forward to meeting one in person, and getting my first Linux instance up and running on one!

Looking to learn more? Product pages and announcements are up, so explore away!