<svg xmlns="http://www.w3.org/2000/svg" version="1.0">
  <defs>
    <pattern id="pattern"
             x="0" y="0" width="200" height="200">
      <circle fill="lime" r="100" cx="100" cy="100"/>
    </pattern>
  </defs>
  <rect width="200" height="200" fill="url(#pattern)"/>
</svg>