<div dir="ltr"><br><font face="arial, sans-serif"><div><span style="font-size:14px">Hi,</span></div><div><span style="font-size:14px">Thanks a lot.</span></div><div><span style="font-size:14px"><br></span></div><div><span style="font-size:14px">I tried option </span></div>
<div><span style="font-size:14px">"set req.hash_ignore_busy = true;"</span></div><div><span style="font-size:14px">in vlc_recv. </span></div><div><span style="font-size:14px">I think it works. But there are side effects: it would increase backend load.</span></div>
<div><span style="font-size:14px"><br></span></div><div><span style="font-size:14px">I have an idea about it in my previous email. what do you think about it?</span></div><div><span style="font-size:14px"><br></span></div>
<div><span style="font-size:14px">Another question is that where can I find the "plus" branch of Varnish which matches this issue.</span></div><div><span style="font-size:14px"><br></span></div><div><span style="font-size:14px"> Any suggestions will be appreciate. </span></div>
<div><span style="font-size:14px">Thanks again for help.</span></div><div><span style="font-size:14px"><br></span></div><div><span style="font-size:14px">Regards,</span></div><div><span style="font-size:14px">--</span></div>
<div><span style="font-size:14px">Shawn Wang</span></div><div><span style="font-size:14px"><br></span></div></font><div><div><div><div><br><div class="gmail_quote">---------- Forwarded message ----------<br>From: <b class="gmail_sendername">Xianzhe Wang</b> <span dir="ltr"><<a href="mailto:wxz19861013@gmail.com">wxz19861013@gmail.com</a>></span><br>
Date: 2013/1/30<br>Subject: Re: How to make multiple clients can get the response at the same time by stream.<br>To: Jakub Słociński <<a href="mailto:kuba@ovh.net">kuba@ovh.net</a>><br><br><br><div dir="ltr"><div>Hi Jakub S.</div>
<div>Thank you very much.</div><div>I tried, and take a simple test, two client request the big file at the same time, they get the response stream immediately, so it works.</div><div>
In that case, multiple requests will go directly to "pass", they do not need to wait, but it would increase backend load. </div><div>We need to balance the benefits and drawbacks.</div><div><br></div><div>I wanna is that:</div>
<div> Client 1 requests url /foo</div><div> Client 2..N request url /foo</div><div> Varnish tasks a worker to fetch /foo for Client 1</div><div> Client 2..N are now queued pending response from the worker</div>
<div> Worker fetch response header(just header not include body) from backend, and find it non-cacheable, then make the remaining requests(Client 2..N) go directly to "pass". And creat the hit_for_pass object synchronously in the first request(Client 1).</div>
<div> Subsequent requests are now given the hit_for_pass object instructing them to go to the backend as long as the hit_for_pass object exists.</div><div><br></div><div>As I mentioned below, is it feasible? Or do you have any Suggestions? </div>
<div><br></div><div>Thanks again for help.</div><div><br></div><div>Regards,</div><div>--</div><div>Shawn Wang</div><div><div style="text-align:justify">
</div><div style="text-align:justify"><font color="#444444" face="sans-serif"><span style="font-size:17px;line-height:21px"><br></span></font></div></div></div><div class=""><div class="h5"><div class="gmail_extra"><br><br>
<div class="gmail_quote">2013/1/29 Jakub Słociński <span dir="ltr"><<a href="mailto:kuba@ovh.net" target="_blank">kuba@ovh.net</a>></span><br>
<blockquote class="gmail_quote" style="margin-top:0px;margin-right:0px;margin-bottom:0px;margin-left:0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">Hi Xianzhe Wang,<br>
you should try option<br>
"set req.hash_ignore_busy = true;"<br>
in vlc_recv.<br>
<br>
Regards,<br>
--<br>
Jakub S.<br>
<br>
<br>
Xianzhe Wang napisał(a):<br>
<div><div>> Hello everyone,<br>
> My varnish version is 3.0.2-streaming release.And I set<br>
> "beresp.do_stream = true" in vcl_fetch in order to "Deliver the object to<br>
> the client directly without fetching the whole object into varnish";<br>
><br>
> This is a part of my *.vcl file:<br>
><br>
> sub vcl_fetch {<br>
> set beresp.grace = 30m;<br>
><br>
> set beresp.do_stream = true;<br>
><br>
> if (beresp.http.Content-Length && beresp.http.Content-Length ~<br>
> "[0-9]{8,}") {<br>
> return (hit_for_pass);<br>
> }<br>
><br>
> if (beresp.http.Pragma ~ "no-cache" || beresp.http.Cache-Control ~<br>
> "no-cache" || beresp.http.Cache-Control ~ "private") {<br>
> return (hit_for_pass);<br>
> }<br>
><br>
> if (beresp.ttl <= 0s ||<br>
> beresp.http.Set-Cookie ||<br>
> beresp.http.Vary == "*") {<br>
><br>
> set beresp.ttl = 120 s;<br>
> return (hit_for_pass);<br>
> }<br>
><br>
> return (deliver);<br>
> }<br>
><br>
> Then I request a big file(about 100M+) like "xxx.zip" from clients.There is<br>
> only one client can access the object.because "the object will marked as<br>
> busy as it is delivered."<br>
><br>
> But if the request goes directly to “pass” ,multiple clients can get the<br>
> response at the same time.<br>
><br>
> Also if I remove<br>
> if (beresp.http.Content-Length && beresp.http.Content-Length ~<br>
> "[0-9]{8,}") {<br>
> return (hit_for_pass);<br>
> }<br>
> to make the file cacheable,multiple clients can get the response at the<br>
> same time.<br>
><br>
> Now I want "multiple clients can get the response at the same time." in all<br>
> situations("pass","hit","hit_for_pass").<br>
><br>
> What can I do for it?<br>
> Any suggestions will be appreciate.<br>
> Thank you.<br>
><br>
> -Shawn Wang<br>
<br>
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<br>
</blockquote></div><br></div>
</div></div></div><br></div></div></div></div></div>