<p></p>
<p dir="auto">I am looking at improving caching and purging for tile.openstreetmap.org see: <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="1877517178" data-permission-text="Title is private" data-url="https://github.com/openstreetmap/operations/issues/947" data-hovercard-type="issue" data-hovercard-url="/openstreetmap/operations/issues/947/hovercard" href="https://github.com/openstreetmap/operations/issues/947">openstreetmap/operations#947</a></p>
<p dir="auto">How much effort would it be to expose the source metatile in a HTTP response header?<br>
eg:</p>
<pre class="notranslate"><code class="notranslate">Surrogate-Key: meta/z/x/y 
</code></pre>
<p dir="auto">Would there be a performance impact?</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br />Reply to this email directly, <a href="https://github.com/openstreetmap/mod_tile/issues/332">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/AA6353VNRXLYSHIG5DLKWB3XYJCQFANCNFSM6AAAAAA4IBM56Y">unsubscribe</a>.<br />You are receiving this because you are subscribed to this thread.<img src="https://github.com/notifications/beacon/AA6353X4NK5HE5Z2FEOXX5LXYJCQFA5CNFSM6AAAAAA4IBM562WGG33NNVSW45C7OR4XAZNFJFZXG5LFVJRW63LNMVXHIX3JMTHG74DJBQ.gif" height="1" width="1" alt="" /><span style="color: transparent; font-size: 0; display: none; visibility: hidden; overflow: hidden; opacity: 0; width: 0; height: 0; max-width: 0; max-height: 0; mso-hide: all">Message ID: <span><openstreetmap/mod_tile/issues/332</span><span>@</span><span>github</span><span>.</span><span>com></span></span></p>
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