What is the minimum amount of RAM required to run Linux kernel on an Embedded device?

linux-kernel embedded kernel linux-device-driver embedded-linux
manav m-n picture manav m-n · Jan 14, 2015 · Viewed 16.7k times · Source

What is the minimum amount of RAM required to run Linux kernel on an Embedded device? In Linux-0.11 for 80x86, the minimum RAM required was 2MB to load the kernel data structures and interrupt vectors.

How much is the minimum needed RAM for present Linux-3.18 kernel? Does different architectures like x86 and ARM have different requirements for minimum RAM required for booting? How does one calculates the same?

Answer

0andriy picture 0andriy · Jan 14, 2015

It's possible to shrink it down to ~600 KiB. Check the work done by Tom Zanussi from Intel. Presentation from Tom and Wiki page about the topic.

UPDATE. Tom published interesting statistics about memory use by different subsystems in the kernel. He did research during that time when he was working on the project.

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