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author Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
date Sat, 12 Apr 2008 20:32:36 -0400
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children d4de13a2546e
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1 \documentclass{beamer}
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2
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3 \usepackage{beamerthemeshadow}
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4
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5 \title{XFS --- The Black Leather Jacket of filesystems}
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6 \author{Josef ``Jeff'' Sipek\\ $<$jeffpc@josefsipek.net$>$}
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7 \date{July 8, 2008}
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8
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9 \begin{document}
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10 \frame{\titlepage}
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11
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12 \AtBeginSection[]
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13 {
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14 \begin{frame}
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15 \frametitle{Outline}
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16 \tableofcontents[currentsection]
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17 \end{frame}
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18 }
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19
Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
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20 \section{History}
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21 \begin{frame}
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22 \frametitle{History: Stoneage (1992)}
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23 \begin{itemize}
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24 \item Berkeley's FFS was state of the art
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25 \item IRIX had EFS (FFS with extents)
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26 \item Many limitations
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27 \begin{itemize}
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28 \item Small file sizes (2 GB)
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29 \item Small filesystem sizes (8GB)
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30 \item Statically allocated metadata
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31 \item Long recovery times
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32 \item Slow operations on large directories
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33 \item No extended attributes
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34 \item No access control lists
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35 \end{itemize}
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36 \end{itemize}
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37 \end{frame}
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38
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39 \begin{frame}
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40 \frametitle{History: Enlightment (1993)}
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41 \begin{center}
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42 \includegraphics[width=0.8\textwidth]{sgi.eps}
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43 \end{center}
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44 \end{frame}
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45
Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
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46 %
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47 % Features
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48 %
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49 \section{Features}
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50 \begin{frame}
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51 \frametitle{Features: Allocation}
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52 \begin{itemize}
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53 \item Delayed allocation
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54 \begin{itemize}
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55 \item Allocate on flush
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56 \item Write reserves disk space, decide where later
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57 \end{itemize}
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58 \item Pre-allocation
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59 \begin{itemize}
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60 \item Reserve space before it is written
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61 \item Minimizes fragmentation
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62 \end{itemize}
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63 \item Direct I/O support
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64 \item Stripe aware allocator
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65 \end{itemize}
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66 \end{frame}
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67
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68 \begin{frame}
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69 \frametitle{Features: Inodes}
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70 \begin{itemize}
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71 \item Dynamically allocated in clusters
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72 \item Inode size is mkfs option
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73 \begin{itemize}
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74 \item 256 Byte (default) -- 4 kByte (max)
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75 \end{itemize}
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76 \item Extended Attributes
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77 \begin{itemize}
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78 \item name=value pairs
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79 \item Used by ACLs, Capabilities, SELinux, DMAPI
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80 \end{itemize}
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81 \end{itemize}
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82 \end{frame}
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83
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84 \begin{frame}
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85 \frametitle{Features: Other}
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86 \begin{itemize}
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87 \item B+ Trees
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88 \item 64-bit
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89 \item Variable block size (512 Bytes -- 64 kB)
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90 \item Allocation Groups
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91 \item Lots of utilities
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92 \item Direct I/O
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93 \item DMAPI
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94 \item EA/ACL
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95 \item online fs growth
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96 \item amazingly fast
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97 \end{itemize}
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98 \end{frame}
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99
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100 \begin{frame}
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101 \frametitle{Why use it?}
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102 \begin{itemize}
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103 \item Stable, mature codebase
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104 \begin{itemize}
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105 \item oldest journaling filesystem on Linux
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106 \end{itemize}
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107 \item Very well performing
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108 \item DMAPI support
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109 \item Good support for EAs / ACLs
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110 \end{itemize}
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111 \end{frame}
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112
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113 \begin{frame}
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114 \frametitle{Why \emph{not} use it?}
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115 \begin{itemize}
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116 \item No data journaling
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117 \item Got time to waste
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118 \end{itemize}
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119 \end{frame}
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120
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121 %
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122 % Demos
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123 %
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124 \section{Demos}
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125 \begin{frame}
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126 \frametitle{\texttt{\textbf{xfsdump}}}
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127 xfsdump ...
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128 \end{frame}
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129
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130 \begin{frame}
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131 \frametitle{\texttt{\textbf{xfsrestore}}}
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132 xfsrestore ...
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133 \end{frame}
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134
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135 \begin{frame}
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136 \frametitle{\texttt{\textbf{mkfs/mount}}}
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137 mkfs/mount
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138 \end{frame}
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139
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140 \begin{frame}
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141 \frametitle{\texttt{\textbf{xfs\_growfs}}}
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142 xfs\_growfs ...
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143 \end{frame}
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144
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145 \begin{frame}
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146 \frametitle{\texttt{\textbf{xfs\_freeze}}}
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147 freeze / unfreeze
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148 \end{frame}
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149
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150 \begin{frame}
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151 \frametitle{\texttt{\textbf{xfs\_check}} \& \texttt{\textbf{xfs\_repair}}}
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152 check / repair
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153 \end{frame}
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154
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155 \begin{frame}
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156 \frametitle{\texttt{\textbf{xfs\_io}}}
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157 xfs\_io ...
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158 \end{frame}
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159
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160 \begin{frame}
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161 \frametitle{\texttt{\textbf{xfs\_quota}}}
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162 xfs\_quota ...
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163 \end{frame}
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164
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165 \begin{frame}
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166 \frametitle{\texttt{\textbf{xfs\_admin}}}
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167 xfs\_admin ...
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168 \end{frame}
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169
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170 \begin{frame}
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171 \frametitle{\texttt{\textbf{xfs\_bmap}}}
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172 xfs\_bmap ...
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173 \end{frame}
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174 %
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175 % Wrap-up
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176 %
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177 \section{}
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178 \begin{frame}
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179 \frametitle{Questions?}
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180 \begin{center}
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181 \includegraphics[width=\textwidth]{xfs.eps}
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182 \end{center}
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183 \end{frame}
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184
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185 \begin{frame}
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186 \frametitle{More info}
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187 \begin{itemize}
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188 \item \url{http://oss.sgi.com/projects/xfs/}
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189 \item \url{xfs@oss.sgi.com}
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190 \item \url{http://oss.sgi.com/projects/xfs/papers/ukuug2003.pdf}
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191 \end{itemize}
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192 \end{frame}
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193
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194 \end{document}