src/main/java/com/google/devtools/build/docgen/templates/attributes/test/size.html

<p><code>String "enormous", "large" "medium" or "small",
default is "medium"; optional; <a href="#configurable-attributes">nonconfigurable</a></code></p>

<p>Specifies a test's "heaviness": how much time/resources it needs to run.</p>

<p>Unit tests are considered "small", integration tests "medium", and end-to-end tests "large" or
"enormous". Bazel uses the size to determine a default timeout, which can be overridden using the
<code>timeout</code> attribute. When the test is run locally, the <code>size</code> is additionally
used for scheduling purposes: Bazel tries to respect <code>--local_{ram,cpu}_resources</code> and
not overwhelm the local machine by running lots of heavy tests at the same time.</p>

<p>Test sizes correspond to the following default timeouts and assumed peak local resource
usages:</p>

<table style="width: 100%">
  <tr>
    <th>Size</th>
    <th>RAM (in MB)</th>
    <th>CPU (in CPU cores)</th>
    <th>Default timeout</th>
  </tr>
  <tr>
    <td>small</td>
    <td>20</td>
    <td>1</td>
    <td>short (1 minute)</td>
  </tr>
  <tr>
    <td>medium</td>
    <td>100</td>
    <td>1</td>
    <td>moderate (5 minutes)</td>
  </tr>
  <tr>
    <td>large</td>
    <td>300</td>
    <td>1</td>
    <td>long (15 minutes)</td>
  </tr>
  <tr>
    <td>enormous</td>
    <td>800</td>
    <td>1</td>
    <td>eternal (60 minutes)</td>
  </tr>
</table>

<p>The environment variable
<a href="../test-encyclopedia.html#initial-conditions"><code>TEST_SIZE</code></a> will be set to the
value of this attribute when spawning the test.</p>