

Ask HN: How does Google Maps transfer '0 byte' images on Street View? - stormbr

I was reading the answer to this question http:&#x2F;&#x2F;stackoverflow.com&#x2F;questions&#x2F;8072921&#x2F;chrome-dev-tools-size-vs-content on Stack Overflow about &#x27;Size&#x27; vs &#x27;Content&#x27; on the Network tab of Chrome, and the accepted answer said:<p>...<p>&quot;Size&quot; is the number of bytes on the wire, and &quot;content&quot; is the actual size of the resource. A number of things can make them different, including:<p>* Being served from cache (small or 0 &quot;size&quot;)<p>* GZip encoding (smaller size than content)<p>* Request&#x2F;Response headers, including cookies (larger size than content)<p>* Redirects or authentication requests<p>...<p>So I was a little surprised when I was checking the network tab on a typical street view page on Google maps and observed that the size of almost every tile (JPEG) was 0 but it wasn&#x27;t being served from a local cache nor was it gzipped.<p>Here&#x27;s what I see (note 6th column, Size&#x2F;Content): http:&#x2F;&#x2F;i.imgur.com&#x2F;VpENUSC.png<p>How is this happening, how can the file they transfer be 0 on the wire but definitely have content (as indicated) without caching or gzipping?<p>I&#x27;d love some more clarification if I&#x27;m misunderstanding something obvious. Thanks!
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stormbr
Clickable links:

[http://stackoverflow.com/questions/8072921/chrome-dev-
tools-...](http://stackoverflow.com/questions/8072921/chrome-dev-tools-size-
vs-content)

[http://i.imgur.com/VpENUSC.png](http://i.imgur.com/VpENUSC.png)

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xoxo
Could be wrong here but from running some tests myself I get 0 size when
loading images from cache but the content stays the same.

I think maybe it's backwards?

