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<p class="MsoNormal">Hello, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We are evaluating varnish to build an internal content delivery network for our company.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We have big http resources which we need to accelerate the delivery of from backend which have really high latency. To work around the latency issue we´d like to use ranged http requests to request the resource in multiple ranged chunks.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Would it be possible to have varnish request the resource from the backend in multiple concurrent chunks from the backend ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I´ve found this way of doing this: <a href="http://devblog.seomoz.org/2011/05/how-to-cache-http-range-requests/">
http://devblog.seomoz.org/2011/05/how-to-cache-http-range-requests/</a> which would work for us if the http client always requests the same ranges, which we cannot guarantee.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The workflow I´m looking for is:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="margin-left:38.25pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Client makes a request to varnish for a resource<o:p></o:p></p>
<p class="MsoListParagraph" style="margin-left:38.25pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>In the case of a cache miss varnish does a vcl_fetch<o:p></o:p></p>
<p class="MsoListParagraph" style="margin-left:38.25pt;text-indent:-.25in;mso-list:l0 level1 lfo2">
<![if !supportLists]><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>The vcl_fetch uses multiple ranged requests to the backend for the resource and merges them into one cache entry and serves to the client.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I should note that we are using the streaming support as well.
<o:p></o:p></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="IS" style="color:#1F497D">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><b><span lang="IS" style="color:#1F497D"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span lang="IS" style="color:#1F497D">Oddur Snær Magnússon<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="IS" style="color:#1F497D">Senior Programmer </span>
<span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D">| Reykjavík | Iceland</span><span lang="IS" style="color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="IS" style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><img border="0" width="470" height="38" id="Picture_x0020_2" src="cid:image001.png@01CD70BD.F6C0E920" alt="Description: Description: Description: Description: cid:DB5C0F43-387B-4CF8-BC6F-B17512BB8251@ccp.ad.local"></span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="IS" style="color:#1F497D">:wq<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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