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Geoffrey Challen
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Showing 3 changed files with 33 additions and 35 deletions
certainty.tex
include/start.tex
maybe.tex
 \section{From Uncertainty to Certainty}
 \label{sec-certainty}
-While \texttt{maybe} allows programmers to specify multiple alternatives, 
-ultimately only one alternative may be used. Either a single, globally best
-alternative must be chosen, 
-or a deterministic decision procedure
-must be selected. Before discussing options for \textit{adapting} an app
-to its runtime environment, we first
-explain our runtime's support for \texttt{maybe} alternatives, including post-mortem
-evaluation and data-collection. 
-%system implements \texttt{maybe} statements and collects data used to tailor or 
-%\textit{adapt} an app to its host environment. 
-Then, we discuss how \texttt{maybe} testing
-enables a variety of different adaptation patterns.
-
-\subsection{Evaluating Alternatives}
-The optional \texttt{better} block of a \texttt{maybe} statement allows 
-programmers to provide app-specific post-mortem logic. However, in many 
-cases, we expect that \texttt{maybe} statements will be used to achieve 
-common objectives such as improving performance or saving energy. 
-To steamline application development, our current
-system assesses \texttt{maybe} statements without a \texttt{better} 
-block in terms of both energy and performance. In cases where one
-alternative is a clear winner in terms of both energy and performance, that alternative will be used---although note that this selection may
-still need to be time-varying since it may depend on exogenous factors.
+While \texttt{maybe} allows programmers to specify multiple alternatives,
+ultimately only one alternative may be used. Either a single, globally best
+alternative must be chosen, or a deterministic decision procedure must be
+selected. Before discussing options for \textit{adapting} an app to its
+runtime environment, we first explain our runtime's support for
+\texttt{maybe} alternatives, including \textit{a posteriori} evaluation and
+data-collection. Then, we discuss how \texttt{maybe} testing enables a
+variety of different adaptation patterns.
+
+\subsection{Evaluating Alternatives} The optional \texttt{evaluate} block of
+a \texttt{maybe} statement allows programmers to provide app-specific
+\textit{a posteriori} evaluation logic. However, in many cases, we expect
+that \texttt{maybe} statements will be used to achieve common objectives such
+as improving performance or saving energy. To steamline application
+development, our current system assesses \texttt{maybe} statements without a
+\texttt{better} block in terms of both energy and performance. In cases where
+one alternative is a clear winner in terms of both energy and performance,
+that alternative will be used---although note that this selection may still
+need to be time-varying since it may depend on exogenous factors.
 Cases where \texttt{maybe} blocks provide an energy-performance tradeoff
 require more investigation to handle. We are exploring several options,
@@ -79,7 +75,7 @@ selection as described in more detail later in this section.
 We next describe the pre- and post-deployment testing that helps developers to
 design an \textit{adaptation} policy, a strategy for ultimately selecting 
-between alternatives.  While the \texttt{maybe} system
+between alternatives. While the \texttt{maybe} system
 automates many of the tedious tasks normally associated with large-scale
 testing, we still provide ways for the developer to guide and even override
 any step in the process.
+\pdfobjcompresslevel=1
 \documentclass[letterpaper,twocolumn]{sig-alternate}
 \usepackage{url,graphicx,multirow,hyperref,color,calc,ulem,threeparttable,tabularx,booktabs,enumitem,comment,subcaption,balance,leading}
 \usepackage{minted}
@@ -24,7 +24,7 @@ maybe {
 ret = fastPowerHungryAlgorithm(input);
 } or {
 ret = slowPowerEfficientAlgorithm(input);
-} analyze {
+} evaluate {
 return { "repeat": false,
 "score" : nanoTime() + powerDrain() }
 }
@@ -69,16 +69,17 @@ statement providing syntactic sugar. \texttt{maybe} function annotations
 allow uncertainty to be expressed at the function level, with the
 alternatives consisting of multiple function definitions with identical
 signatures. Finally, \texttt{maybe} blocks that require special performance
-evaluation logic can include that in the form of a \texttt{better} statement
-following the main \texttt{maybe} block, as shown in the final example.
-\texttt{better} blocks provide application-specific logic that analyze the
-selected execution path. The \texttt{better} block must return a single JSON
-object that includes two components: A score, with smaller being interpreted
-as better; and a boolean indicating whether the system should use the same
-branch next time, or if it is free to try another. Note that hints and
-dedicated evaluation logic can also be applied to variable and function-level
-\texttt{maybe} statements through annotations. We will return to post-mortem
-evaluation in Section~\ref{sec-certainty}.
+evaluation logic can include that in the form of a \texttt{evaluate}
+statement following the main \texttt{maybe} block, as shown in the final
+example. \texttt{evaluate} blocks provide app-specific \textit{a posteriori}
+logic to evaluate the selected alternative. The \texttt{evaluate} block must
+return a single JSON object that includes two components: A score, with
+smaller being interpreted as better; and a boolean indicating whether the
+system should use the same branch next time, or if it is free to try another.
+Note that hints and dedicated evaluation logic can also be applied to
+variable and function-level \texttt{maybe} statements through annotations. We
+will return to \textit{a posteriori} evaluation in
+Section~\ref{sec-certainty}.
 \subsection{Discussion}