<div dir="ltr">Good question. This is because by default varnish streams the response, so it starts sending what it has, even though it's unsure it can actually deliver. When the eviction strikes, it just aborts the transaction.<div><br></div><div>The problem with "just" passing the data to the user is that there may be more than one and things get really complicated.</div><div><br></div><div>Getting a bigger cache would help, and segregating the storages (smaller than 1MB, and bigger than 1MB for example) would too<br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div>-- <br></div>Guillaume Quintard<br></div></div></div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, May 8, 2020 at 11:28 AM Batanun B <<a href="mailto:batanun@hotmail.com">batanun@hotmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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also... could you explain this part for me? "<span style="color:rgb(32,31,30);font-size:15px;background-color:rgb(255,255,255);display:inline">so
it had to truncate it and throw it away"</span></div>
<div style="font-family:Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
<span style="color:rgb(32,31,30);font-size:15px;background-color:rgb(255,255,255);display:inline">Why
does it have to truncate it? Why not avoid caching it, and returning it as is, from the backend, untouched?</span></div>
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<div id="gmail-m_2763874099659638374divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Guillaume Quintard <<a href="mailto:guillaume@varnish-software.com" target="_blank">guillaume@varnish-software.com</a>><br>
<b>Sent:</b> Friday, May 8, 2020 7:34 PM<br>
<b>To:</b> Batanun B <<a href="mailto:batanun@hotmail.com" target="_blank">batanun@hotmail.com</a>><br>
<b>Cc:</b> <a href="mailto:varnish-misc@varnish-cache.org" target="_blank">varnish-misc@varnish-cache.org</a> <<a href="mailto:varnish-misc@varnish-cache.org" target="_blank">varnish-misc@varnish-cache.org</a>><br>
<b>Subject:</b> Re: Varnish intermittently returns incomplete images</font>
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<div dir="ltr">Hi,
<div><br>
</div>
<div>Do you have objects that are sensibly smaller that your images in your cache?</div>
<div><br>
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<div>What you are describing sounds like LRU failure (check nuke_limit in "varnishadm param.show"), basically, on a miss, varnish couldn't evict enough objects and make room for the new object, so it had to truncate it and throw it away.</div>
<div><br>
</div>
<div>If that's the issue, you can increase nuke_limit, or get a bigger cache, or segregate small and large objects into different storages.</div>
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<div>-- <br>
</div>
Guillaume Quintard<br>
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<div dir="ltr">On Fri, May 8, 2020 at 10:14 AM Batanun B <<a href="mailto:batanun@hotmail.com" target="_blank">batanun@hotmail.com</a>> wrote:<br>
</div>
<blockquote style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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<div style="font-family:Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
Our Varnish (test environment) intermittently returns incomplete images. So the binary content is not complete. When requesting the image from the backend directly (using curl), the complete image is returned every time (I tested 1000 times using a script).</div>
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<br>
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<div style="font-family:Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
This happens intermittently. Sometimes Varnish returns the complete image, sometimes half of it, sometimes 20% etc... The incomplete image is returned quickly, so I don't think there is a timeout involved (we have not configured any specific timeout in varnish).</div>
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<div style="font-family:Calibri,Helvetica,sans-serif;font-size:12pt;color:rgb(0,0,0)">
I see nothing special in varnishlog when this happens. But I don't know how to troubleshoot this in a good way. Any suggestions?</div>
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