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marchyo

Performance

CPU mitigations

Section titled “CPU mitigations”
Option Type Default Description
marchyo.performance.disableMitigations bool true Disable CPU vulnerability mitigations for maximum performance 
marchyo.performance.disableMitigations = true;

To keep mitigations enabled:

marchyo.performance.disableMitigations = false;

Kernel selection

Section titled “Kernel selection”
Option Type Default Description
marchyo.performance.kernel enum "default" Kernel variant: default (nixpkgs LTS default), latest, zen, xanmod, lts 
marchyo.performance.kernel = "zen";

Set via lib.mkDefault, so hosts can still override boot.kernelPackages directly. "default" leaves the option unmanaged.

Kernel & I/O tuning

Section titled “Kernel & I/O tuning”

Opt-in kernel/sysctl/IO tuning for throughput-oriented workloads. Disabled by default. Enabling marchyo.performance.tuning.enable turns on the broadly-safe sub-toggles (network, nvme, memory); the aggressive toggles (hugePages, compute) stay off and must be opted into explicitly.

Option Type Default Description
marchyo.performance.tuning.enable bool false Master switch; enables the safe sub-toggles below
marchyo.performance.tuning.network.enable bool follows enable BBR congestion control, TCP Fast Open, MTU probing, larger socket buffers
marchyo.performance.tuning.nvme.enable bool follows enable NVMe udev tuning: no-op scheduler, larger read-ahead and max request size
marchyo.performance.tuning.memory.enable bool follows enable Lower swappiness, keep FS metadata cached, byte-based dirty-page thresholds
marchyo.performance.tuning.memory.dirtyBytes positive int 268435456 vm.dirty_bytes (256 MiB) — synchronous writeback threshold
marchyo.performance.tuning.memory.dirtyBackgroundBytes positive int 67108864 vm.dirty_background_bytes (64 MiB) — background writeback threshold
marchyo.performance.tuning.hugePages.enable bool false 2 MiB transparent huge pages always
marchyo.performance.tuning.compute.enable bool false Relaxed PAM limits (memlock/rtprio/nofile/nproc) for trusted compute hosts 
# Safe defaults (network + nvme + memory):
marchyo.performance.tuning.enable = true;


# Compute/CUDA workstation — opt into the aggressive toggles too:
marchyo.performance.tuning = {
  enable = true;
  hugePages.enable = true;
  compute.enable = true;
};