--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/paper/fig/twice.svg	Mon Jul 09 10:41:54 2018 +0900
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+		<text><tspan font-family="Arial" > 0</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M80.2,379.0 L89.2,379.0 M556.7,379.0 L547.7,379.0  '/>	<g transform="translate(71.9,382.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="end">
+		<text><tspan font-family="Arial" > 200</tspan></text>
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+		<text><tspan font-family="Arial" > 400</tspan></text>
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+		<text><tspan font-family="Arial" > 600</tspan></text>
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+		<text><tspan font-family="Arial" > 800</tspan></text>
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+		<text><tspan font-family="Arial" > 1000</tspan></text>
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+		<text><tspan font-family="Arial" > 1200</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M110.0,444.0 L110.0,435.0 M110.0,54.1 L110.0,63.1  '/>	<g transform="translate(110.0,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >1 cpu</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M169.5,444.0 L169.5,435.0 M169.5,54.1 L169.5,63.1  '/>	<g transform="translate(169.5,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >2 cpus</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M229.1,444.0 L229.1,435.0 M229.1,54.1 L229.1,63.1  '/>	<g transform="translate(229.1,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >4 cpus</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M288.7,444.0 L288.7,435.0 M288.7,54.1 L288.7,63.1  '/>	<g transform="translate(288.7,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >8 cpus</tspan></text>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M348.2,444.0 L348.2,435.0 M348.2,54.1 L348.2,63.1  '/>	<g transform="translate(348.2,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >16 cpus</tspan></text>
+	</g>
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M407.8,444.0 L407.8,435.0 M407.8,54.1 L407.8,63.1  '/>	<g transform="translate(407.8,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >32 cpus</tspan></text>
+	</g>
+</g>
+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M467.4,444.0 L467.4,435.0 M467.4,54.1 L467.4,63.1  '/>	<g transform="translate(467.4,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >gpu</tspan></text>
+	</g>
+</g>
+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M526.9,444.0 L526.9,435.0 M526.9,54.1 L526.9,63.1  '/>	<g transform="translate(526.9,465.9)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >gpu(kernel only)</tspan></text>
+	</g>
+</g>
+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
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+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<path stroke='black'  d='M80.2,54.1 L80.2,444.0 L556.7,444.0 L556.7,54.1 L80.2,54.1 Z  '/></g>
+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<g transform="translate(16.3,249.1) rotate(270)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >time(ms)</tspan></text>
+	</g>
+</g>
+<g fill="none" color="black" stroke="currentColor" stroke-width="1.00" stroke-linecap="butt" stroke-linejoin="miter">
+	<g transform="translate(318.4,31.0)" stroke="none" fill="black" font-family="Arial" font-size="12.00"  text-anchor="middle">
+		<text><tspan font-family="Arial" >twice benchmark</tspan></text>
+	</g>
+</g>
+	<g id="gnuplot_plot_1" ><title>gnuplot_plot_1</title>
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