Add 12 lattice diagrams to explain CRDTs and quorums

15 files changed, 6658 insertions, 11 deletions

diff --git a/doc/talks/2023-01-18-tocatta/Makefile b/doc/talks/2023-01-18-tocatta/Makefile
index 4a967d24..a1f76e15 100644
--- a/doc/talks/2023-01-18-tocatta/Makefile
+++ b/doc/talks/2023-01-18-tocatta/Makefile
@@ -4,6 +4,18 @@ ASSETS=assets/consistent_hashing_1.pdf \
 	   assets/consistent_hashing_4.pdf \
 	   assets/garage_tables.pdf \
 	   assets/consensus.pdf_tex \
+	   assets/lattice1.pdf_tex \
+	   assets/lattice2.pdf_tex \
+	   assets/lattice3.pdf_tex \
+	   assets/lattice4.pdf_tex \
+	   assets/lattice5.pdf_tex \
+	   assets/lattice6.pdf_tex \
+	   assets/lattice7.pdf_tex \
+	   assets/lattice8.pdf_tex \
+	   assets/lattice9.pdf_tex \
+	   assets/latticeA.pdf_tex \
+	   assets/latticeB.pdf_tex \
+	   assets/latticeC.pdf_tex \
 	   assets/deuxfleurs.pdf
 
 talk.pdf: talk.tex $(ASSETS)
diff --git a/doc/talks/2023-01-18-tocatta/assets/lattice1.svg b/doc/talks/2023-01-18-tocatta/assets/lattice1.svg
new file mode 100644
index 00000000..8bfa5aa7
--- /dev/null
+++ b/doc/talks/2023-01-18-tocatta/assets/lattice1.svg
@@ -0,0 +1,433 @@
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new file mode 100644
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diff --git a/doc/talks/2023-01-18-tocatta/assets/lattice6.svg b/doc/talks/2023-01-18-tocatta/assets/lattice6.svg
new file mode 100644
index 00000000..176b1715
--- /dev/null
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+         id="tspan3748-65"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="73.643356">$\to \{\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan4278"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
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+  </g>
+</svg>
diff --git a/doc/talks/2023-01-18-tocatta/assets/lattice7.svg b/doc/talks/2023-01-18-tocatta/assets/lattice7.svg
new file mode 100644
index 00000000..7ce8bda8
--- /dev/null
+++ b/doc/talks/2023-01-18-tocatta/assets/lattice7.svg
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+    <text
+       xml:space="preserve"
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+         id="tspan3748"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="24.042637">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
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+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="33.02087">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#999999;stroke-width:0.264583"
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+       id="text3750-0"><tspan
+         sodipodi:role="line"
+         id="tspan3748-6"
+         style="fill:#999999;stroke-width:0.264583"
+         x="23.457415"
+         y="41.972523">$\not\sqsupseteq \{a\}$</tspan></text>
+    <circle
+       style="fill:#ff0000;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-6-6-4"
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+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+       y="73.643356"
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+         sodipodi:role="line"
+         id="tspan3748-65"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="73.643356">$\to \{\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan4278"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="52.022549">return OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan4278-7"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="92.005798">return $\{\}\sqcup\{a\}=\{a\}$</tspan></text>
+    <circle
+       style="fill:#800080;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-1-5"
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+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+       y="83.577797"
+       id="text3750-0-6"><tspan
+         sodipodi:role="line"
+         id="tspan3748-6-9"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="83.577797">$\to \{a\}$</tspan></text>
+  </g>
+</svg>
diff --git a/doc/talks/2023-01-18-tocatta/assets/lattice8.svg b/doc/talks/2023-01-18-tocatta/assets/lattice8.svg
new file mode 100644
index 00000000..3bada791
--- /dev/null
+++ b/doc/talks/2023-01-18-tocatta/assets/lattice8.svg
@@ -0,0 +1,587 @@
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+    <text
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+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#999999;stroke-width:0.264583"
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+         id="tspan3748-6-7"
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diff --git a/doc/talks/2023-01-18-tocatta/assets/lattice9.svg b/doc/talks/2023-01-18-tocatta/assets/lattice9.svg
new file mode 100644
index 00000000..8b3c6585
--- /dev/null
+++ b/doc/talks/2023-01-18-tocatta/assets/lattice9.svg
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new file mode 100644
index 00000000..400ccff8
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new file mode 100644
index 00000000..06725d75
--- /dev/null
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index 00000000..c815af94
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+       id="text3707"><tspan
+         sodipodi:role="line"
+         id="tspan3705"
+         style="stroke-width:0.264583;fill:#000000"
+         x="6.9525447"
+         y="13.702217">$write(\{a\})$:</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan3748"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="24.042637">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="33.02087">$\sqsupseteq \{a\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan3748-6"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="41.972523">$\sqsupseteq \{a\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         id="tspan4278"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="52.022549">return OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="14.395845"
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+         id="tspan4278-8"
+         style="fill:#000000;stroke-width:0.264583"
+         x="14.395845"
+         y="102.48464">return OK</tspan></text>
+    <circle
+       style="fill:#ff0000;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
+       id="path3663-1-4"
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+       style="fill:#800080;stroke:none;stroke-width:0.499999;stroke-dasharray:none;stop-color:#000000"
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+         y="65.279381">$write(\{b\})$:</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         sodipodi:role="line"
+         id="tspan3748-4"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="75.619804">$\sqsupseteq \{b\}$</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
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+         sodipodi:role="line"
+         id="tspan3748-2-3"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="84.598038">$\sqsupseteq \{b\} \to$ OK</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-size:8.46667px;line-height:1.25;font-family:sans-serif;fill:#000000;stroke-width:0.264583"
+       x="23.457415"
+       y="93.54969"
+       id="text3750-0-0"><tspan
+         sodipodi:role="line"
+         id="tspan3748-6-7"
+         style="fill:#000000;stroke-width:0.264583"
+         x="23.457415"
+         y="93.54969">$\sqsupseteq \{b\} \to$ OK</tspan></text>
+  </g>
+</svg>
diff --git a/doc/talks/2023-01-18-tocatta/talk.pdf b/doc/talks/2023-01-18-tocatta/talk.pdf
index ba9bde3d..02f605e8 100644
--- a/doc/talks/2023-01-18-tocatta/talk.pdf
+++ b/doc/talks/2023-01-18-tocatta/talk.pdf
diff --git a/doc/talks/2023-01-18-tocatta/talk.tex b/doc/talks/2023-01-18-tocatta/talk.tex
index ac9b4077..e789f597 100644
--- a/doc/talks/2023-01-18-tocatta/talk.tex
+++ b/doc/talks/2023-01-18-tocatta/talk.tex
@@ -494,8 +494,7 @@
 			\item \textbf{Linearizability} of all operations\\
 				(strongest consistency guarantee)
 				\vspace{1em}
-			\item \textbf{Replicated state machines} that can implement
-				any sequential specification
+			\item Any sequential specification can be implemented as a \textbf{replicated state machine}
 				\vspace{1em}
 			\item \textbf{Costly}, the leader is a bottleneck;
 				leader elections on failure take time
@@ -515,7 +514,7 @@
 			\item \textbf{Operations have to commute}, i.e.~we
 				can only implement CRDTs
 				\vspace{1em}
-			\item \textbf{Fast}, no node is a bottleneck;\\
+			\item \textbf{Fast}, no single bottleneck;\\
 				works the same with offline nodes
 		\end{itemize}
 	} \end{minipage}
@@ -530,27 +529,29 @@
 	\vspace{2em}
 
 	\hspace{1em}
-	\begin{minipage}{7cm}
+	\begin{minipage}{6.5cm}
 		\underline{Consensus-based systems:}
 
 		\vspace{1em}
 
 		\textbf{Any sequential specification}\\~
+
+		\vspace{1em}
+		\textbf{Easier to program for}: just write your program as if it were sequential on a single machine
+
 	\end{minipage}
 	\hfill
-	\begin{minipage}{7cm}
+	\begin{minipage}{6.5cm}
 		\underline{Weakly consistent systems:}
 
 		\vspace{1em}
 		
 		\textbf{CRDTs only}\\(conflict-free replicated data types)
+
+		\vspace{1em}
+		Part of the complexity is \textbf{reported to the consumer of the API}\\~
 	\end{minipage}
 	\hspace{1em}
-
-	\vspace{3em}
-	\begin{center}
-		Part of the complexity is \textbf{reported to the consumer of the API}
-	\end{center}
 \end{frame}
 
 \begin{frame}
@@ -663,7 +664,27 @@
 \end{frame}
 
 \begin{frame}
-	\frametitle{Impact on performances}
+	\frametitle{Understanding CRDTs and quorums}
+	\begin{figure}
+		\centering
+		\def\svgwidth{.8\textwidth}
+		\only<1>{\import{assets/}{lattice1.pdf_tex}}%
+		\only<2>{\import{assets/}{lattice2.pdf_tex}}%
+		\only<3>{\import{assets/}{lattice3.pdf_tex}}%
+		\only<4>{\import{assets/}{lattice4.pdf_tex}}%
+		\only<5>{\import{assets/}{lattice5.pdf_tex}}%
+		\only<6>{\import{assets/}{lattice6.pdf_tex}}%
+		\only<7>{\import{assets/}{lattice7.pdf_tex}}%
+		\only<8>{\import{assets/}{lattice8.pdf_tex}}%
+		\only<9>{\import{assets/}{lattice9.pdf_tex}}%
+		\only<10>{\import{assets/}{latticeA.pdf_tex}}%
+		\only<11>{\import{assets/}{latticeB.pdf_tex}}%
+		\only<12>{\import{assets/}{latticeC.pdf_tex}}%
+	\end{figure}
+\end{frame}
+
+\begin{frame}
+	\frametitle{Performance gains in practice}
 		\begin{center}
 			\includegraphics[width=.8\linewidth]{assets/endpoint-latency-dc.png}
 		\end{center}