Appendix B. Supported kdump Configurations and Targets

B.1. Memory Requirements for kdump

In order for kdump to be able to capture a kernel crash dump and save it for further analysis, a part of the system memory has to be permanently reserved for the capture kernel. The table below contains a list of minimum memory requirements for kdump based on the system's architecture and total available physical memory.
For information on how to change memory settings on the command line, see Section 2.2.1, “Configuring the Memory Usage”. For instructions on how to set up the amount of reserved memory in the graphical user interface, see Section 2.3.1, “Configuring the Memory Usage”.

Table B.1. Minimum Amount of Reserved Memory Required for kdump

Architecture Available Memory Minimum Reserved Memory
AMD64 and Intel 64 (x86_64) 2 GB and more 160 MB + 2 bits for every 4 KB of RAM. For a system with 1 TB of memory, 224 MB is the minimum (160 + 64 MB).
IBM POWER (ppc64) 2 GB to 4 GB 256 MB of RAM.
4 GB to 32 GB 512 MB of RAM.
32 GB to 64 GB 1 GB of RAM.
64 GB to 128 GB 2 GB or RAM.
128 GB and more 4 GB of RAM.
IBM System z (s390x) 2 GB and more 160 MB + 2 bits for every 4 KB of RAM. For a system with 1 TB of memory, 224 MB is the minimum (160 + 64 MB).