What are the memory and CPU limits of the largesmp kernel in Red Hat Enterprise Linux 4?
In the currently used Red Hat version 4 (update 3 and later), Red Hat provides a kernel supporting large numbers of CPUs. It is named kernel-largesmp-2.6.9-xxx.EL.yyy.rpm (xxx is the kernel version and yyy the platform name). It supports three platforms: x86_64, ia64, and ppc64.
x86_64 refers to EM64T or AMD64 CPUs.
ia64 refers to Itanium CPUs.
ppc64 refers to Power PC CPUs.
This kernel is installed automatically when installing Red Hat on a machine with 8 or more CPUs.
The table below shows the CPU and memory limits supported by kernel-largesmp.
CPU Supported/Certified/Theoretical Limits with the Largesmp Kernel on 64-bit Platforms
| Red Hat Enterprise Linux 4 Update 3 | |||
|---|---|---|---|
| Supported CPUs | Certified CPUs | Theoretical CPUs (NR_CPU) | |
| x86_64 | 64 | 64 | 64 |
| Itanium | 64 | 256 | 512 |
| POWER | 64 | 128 | 128 |
Memory Supported with the Largesmp Kernel on 64-bit Platforms
| Red Hat Enterprise Linux 4 Update 3 | |||
|---|---|---|---|
| Supported Memory | Theoretical Memory | ||
| x86_64 | 128 GB | 1 TB | |
| Itanium | 256 GB | 1024 TB | |
| POWER | 256 GB | 2 TB |
