func setMemory(dirPath string, r *cgroups.Resources) error {
	if !isMemorySet(r) {
		return nil
	}

	if err := CheckMemoryUsage(dirPath, r); err != nil {
		return err
	}

	swap, err := cgroups.ConvertMemorySwapToCgroupV2Value(r.MemorySwap, r.Memory)
	if err != nil {
		return err
	}
	swapStr := numToStr(swap)
	if swapStr == "" && swap == 0 && r.MemorySwap > 0 {
		// memory and memorySwap set to the same value -- disable swap
		swapStr = "0"
	}
	// never write empty string to `memory.swap.max`, it means set to 0.
	if swapStr != "" {
		if err := cgroups.WriteFile(dirPath, "memory.swap.max", swapStr); err != nil {
			// If swap is not enabled, silently ignore setting to max or disabling it.
			if !(errors.Is(err, os.ErrNotExist) && (swapStr == "max" || swapStr == "0")) { //nolint:staticcheck // Ignore "QF1001: could apply De Morgan's law".
				return err
			}
		}
	}

	if val := numToStr(r.Memory); val != "" {
		if err := cgroups.WriteFile(dirPath, "memory.max", val); err != nil {
			return err
		}
	}

	// cgroup.Resources.KernelMemory is ignored

	if val := numToStr(r.MemoryReservation); val != "" {
		if err := cgroups.WriteFile(dirPath, "memory.low", val); err != nil {
			return err
		}
	}

	return nil
}

Warm-up