Example
<svg width="400" height="400">
<defs>
<pattern id="pattern1" width="0.2" height="0.2" patternUnits="objectBoundingBox">
<circle cx="10" cy="10" r="10" fill="#0000ff" />
</pattern>
</defs>
<rect x="10" y="10" width="100" height="100" stroke="black" fill="url(#pattern1)"/>
</svg>
