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@@ -4,7 +4,7 @@
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In this section, we describe our execution model and its implications for software design.
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Sec.~\ref{sec:system_description} introduces the target architecture and the reference system used for evaluations.
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Sec.~\ref{sec:execution_model} presents our execution model, derived from key observations obtained through experimental results.
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-In the subsequent three sections, we discuss how this model affects both the power efficiency and correctness of software design.
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+In the following three sections, we discuss how this model affects both the power efficiency and correctness of software design.
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Finally, in Sec.~\ref{sec:other_architectures}, we evaluate the effectiveness of our model across systems with various architectural configurations.
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\subsection{Target Architecture and Reference System}
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@@ -203,11 +203,11 @@ In Sec.~\ref{sec:use_vdd_for_checkpoint}, we validate this aspect and propose me
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\subsection{Impact of Sub-normal Voltage Execution}
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\label{sec:sub_normal_execution}
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-The traditional model leads the software designers to assume that the system is executed under a stable voltage.
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+The traditional model leads software designers to assume that the system is executed under a stable voltage.
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However, a significant portion of execution may happen after the power-off threshold at sub-normal voltages (\textbf{O3}), as discussed in Sec.~\ref{sec:predicting_power_failures}.
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Being aware of this is crucial to software designers since analog components and peripherals may function differently at sub-normal voltages.
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-
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Two relevant examples are Analog-Digital Converters (ADCs) and external NVMs.
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+
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ADCs are commonly used to determine when to execute a checkpoint by reading $V_{ES}$.
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It quantizes the input analog voltage into discrete $2^n$ values, ranging from 0 to the given reference voltage, where $n$ is a resolution.
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Using smaller reference voltage increases sensitivity of ADC at the cost of reduced representation range.
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@@ -233,7 +233,7 @@ Using smaller reference voltage increases sensitivity of ADC at the cost of redu
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\label{fig:adc_and_fram_error}
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\end{figure}
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-Fig.~\ref{fig:adc_error} shows the behavior of ADCs in sub-normal voltages.
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+Fig.~\ref{fig:adc_error} shows the behavior of ADCs, where the execution in sub-normal voltages are depicted in gray.
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% ADC quantizes the input analog voltage into discrete $2^n$ values, ranging from 0 to the given reference voltage, where $n$ is a resolution.
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% Therefore, using smaller reference voltage increases sensitivity of ADC at the cost of reduced representation range.
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% Since $n$ is fixed, using smaller reference voltage increases sensitivity of the ADC at the cost of reduced representation range.
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@@ -280,7 +280,7 @@ Table~\ref{tab:architectures} shows the detailed parameters of the target archit
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A1 shares the same configuration as the reference system but equips MRAM (Everspin MR5A16ACYS35), which is gaining attention as a next generation NVM~\cite{akhunovEnabling2023,bakarProtean2023a,dewinkelIntermittentlypowered2022,wuIntOS2024}, instead of FRAM.
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% This setup is included since MRAM is also gaining attention as a next generation NVM~\cite{akhunovEnabling2023,bakarProtean2023a,dewinkelIntermittentlypowered2022,wuIntOS2024}.
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Second target is MSP430 equipped with on-chip FRAM, a widely adopted 16-bit platform in intermittent system research.
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-For both systems, the architectural parameters are set to achieve an operation time of approximately 50 ms.
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+For both systems, the architectural parameters are configured to achieve an operation time of approximately 50 ms.
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\begin{figure}
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\centering
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