config-linux: mark memory.kernel[TCP] as NOT RECOMMENDED#1093
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tianon merged 1 commit intoopencontainers:masterfrom Mar 8, 2021
Merged
config-linux: mark memory.kernel[TCP] as NOT RECOMMENDED#1093tianon merged 1 commit intoopencontainers:masterfrom
tianon merged 1 commit intoopencontainers:masterfrom
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Per-cgroup kernel memory accounting (and explicit limiting) is problematic in the Linux kernel for too many reasons to quote here. Besides, cgroup v2 does not even have a kernel memory limit knob, and the one in cgroup v1 is made obsoleted in kernel v5.4 [1]. Mark memory.kernel and memory.kernelTCP as NOT RECOMMENDED, in additon to OPTIONAL. This is a way to say "we do not anyone (runtimes or users) to set those limits, unless they have good understanding and strong reasons to do so". [1] torvalds/linux@0158115f702b0ba208ab0b Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
thaJeztah
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Mar 8, 2021
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| * **`kernel`** *(int64, OPTIONAL, NOT RECOMMENDED)* - sets hard limit for kernel memory | ||
| * **`kernelTCP`** *(int64, OPTIONAL, NOT RECOMMENDED)* - sets hard limit for kernel TCP buffer memory |
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Wondering if it would be better to mark them as "deprecated" (as they're deprecated in the Kernel); kept for backward compatibility by runtimes are allowed to ignore them
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- We're using the terms (OPTIONAL, NOT RECOMMENDED) as per RFC2119, and there's no such term as "DEPRECATED" in its lexicon.
- This spec (if I understand it right) is for both runtimes and their users. Saying "OPTIONAL" means users can chose to not set these limits, and runtimes can ignore the set limits. Saying NOT RECOMMENDED means users and runtimes should not set those limits, unless there's a good understanding and some compelling reasons to do so.
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LGTM |
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This was referenced Sep 16, 2025
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Per-cgroup kernel memory accounting (and explicit limiting) is
problematic in the Linux kernel for too many reasons to quote here.
Besides, cgroup v2 does not even have a kernel memory limit knob,
and the one in cgroup v1 is made obsoleted in kernel v5.4 [1].
Mark memory.kernel and memory.kernelTCP as NOT RECOMMENDED, in additon
to OPTIONAL. This is a way to say "we do not anyone (runtimes or users)
to set those limits, unless they have good understanding and strong
reasons to do so".
[1]torvalds/linux@0158115f702b0ba208ab0