User Kernel split in 64bit Linux

Question

What is the default user/kernel split in the 64bit linux ?

I read Documentation/x86_64/mm.txt (which someone pointed out), but I could not make out. Can somebody provide a direct answer (something like 3GB/1GB for 32bit implementation).

Do you mean the split for memory? – Kevin Feb 21 '12 at 15:29 — Kevin, Feb 21 '12 at 15:29
@Kevin Yes. I meant the split of the memory. – Kris srini Feb 22 '12 at 06:11 — Kris srini, Feb 22 '12 at 06:11

score 8 · Answer 1 · edited Mar 26 '12 at 00:15

8

Like the docs say, user space gets 2⁴⁷ bytes = 128TiB, and kernel gets 512MiB. The rest of the address space goes to various parts of the system, along with a few unusable holes.

edited Mar 26 '12 at 00:15

Gilles 'SO- stop being evil'

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answered Feb 21 '12 at 07:51

Ignacio Vazquez-Abrams

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64bit kernel gets less memory than 32bit, why? – Ted Jun 21 '22 at 08:07

User Kernel split in 64bit Linux

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