<div dir="ltr">It's not a requirement in any way and your SEO might turn out just fine using different subdomains. My suggestion is not just made up from my imagination, but advice from a Google employee since this have been a real problem for us. By serving the same image from multiple subdomains, from the same page the image can end up in a kind of "limbo" where google can't decide which image to use.<br><div><br></div><div>Also, as I understand it, canonical headers are currently only supported for web search and not image search from reading this doc <a href="https://support.google.com/webmasters/answer/139066?hl=en" target="_blank">https://support.google.com/webmasters/answer/139066?hl=en</a> .</div><div><br></div><div>Again, this might not even be relevant for your case, Dennis :)</div><div dir="ltr"><div><br></div><div>~ Nikolaj</div></div><br><div class="gmail_quote">On Mon, May 11, 2015 at 9:40 AM Lucas Rolff <<a href="mailto:lucas@slcoding.com" target="_blank">lucas@slcoding.com</a>> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">It's not really required
to serve it from the same sub-domain always.<br>
The most optimal solution would be to add the canonical link header when
serving using domain sharding.<br>
<br>
But from a caching perspective, keeping the sharding consistent is
indeed beneficial (you can use crc32 on the image name e.g. this will
always return the same hash, and based on this do the domain sharding),
but from a SEO perspective, it doesn't matter if you just do it right
with canonical link.<br>
<br>
<blockquote style="border:0px none" type="cite">
<div style="margin:30px 25px 10px 25px"><div style="display:table;width:100%;border-top:1px solid #edeef0;padding-top:5px"> <div style="display:table-cell;vertical-align:middle;padding-right:6px"><img src="cid:part1.02070200.02050906@slcoding.com" name="msg-f:1500863175665744936_msg-f:1500858319503376548_postbox-contact.jpg" height="25px" width="25px"></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle;width:100%">
<a href="mailto:sjums07@gmail.com" style="color:#737f92!important;padding-right:6px;font-weight:bold;text-decoration:none!important" target="_blank">Nikolaj Schomacker</a></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle">
<font color="#9FA2A5"><span style="padding-left:6px">11 May 2015 08:49</span></font></div></div></div>
<div style="color:#888888;margin-left:24px;margin-right:24px"></div></blockquote></div><div bgcolor="#FFFFFF" text="#000000"><blockquote style="border:0px none" type="cite"><div style="color:#888888;margin-left:24px;margin-right:24px"><div dir="ltr">And a last thing
you should be aware of if it applies to your case is SEO. Using
multiple domains for images is perfectly fine in the eyes of Google, but
be sure the same images is always served from the same subdomain. Also
be sure to have all of the subdomains added to the same webmasters
account as your main site.<br><div><br></div><div>~ Nikolaj</div></div><br>
</div></blockquote></div><div bgcolor="#FFFFFF" text="#000000"><blockquote style="border:0px none" type="cite"><div style="color:#888888;margin-left:24px;margin-right:24px"><div>_______________________________________________<br>nginx mailing
list<br><a href="mailto:nginx@nginx.org" target="_blank">nginx@nginx.org</a><br><a href="http://mailman.nginx.org/mailman/listinfo/nginx" target="_blank">http://mailman.nginx.org/mailman/listinfo/nginx</a></div></div></blockquote></div><div bgcolor="#FFFFFF" text="#000000"><blockquote style="border:0px none" type="cite"><div style="color:#888888;margin-left:24px;margin-right:24px"></div>
<div style="margin:30px 25px 10px 25px"><div style="display:table;width:100%;border-top:1px solid #edeef0;padding-top:5px"> <div style="display:table-cell;vertical-align:middle;padding-right:6px"><img src="cid:part2.09070403.09020607@slcoding.com" name="msg-f:1500863175665744936_msg-f:1500858319503376548_postbox-contact.jpg" height="25px" width="25px"></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle;width:100%">
<a href="mailto:lucas@slcoding.com" style="color:#737f92!important;padding-right:6px;font-weight:bold;text-decoration:none!important" target="_blank">Lucas Rolff</a></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle">
<font color="#9FA2A5"><span style="padding-left:6px">9 May 2015 20:24</span></font></div></div></div></blockquote></div><div bgcolor="#FFFFFF" text="#000000"><blockquote style="border:0px none" type="cite">
<div style="color:#888888;margin-left:24px;margin-right:24px">
What you should do, to
increase the concurrent amount of requests, is to use domain-sharding,
since as Paul mentioned, browsers have between 4 and 8 (actually)
simultaneous connections per domain, meaning if you introduce
static1,2,<a href="http://3.domain.com" target="_blank">3.domain.com</a>, you will increase your concurrency.<br>
<br>
But at same time you also need to be aware, that this can have a
negative effect on your performance if you put too many domains, there's
no golden rule on how many you need, it's all a site by site case, and
it differs.<br>
Also take into account your end-users connection can be limiting things
heavily as well if you put too much concurrency (thus negative effect) -
if you have a high number of concurrent requests being processed it
will slow down the download time of each, meaning the perceived
performance that the user see might get worse because it feels like the
page is slower.<br>
<br>
- Lucas<br>
<br>
</div>
<div style="margin:30px 25px 10px 25px"><div style="display:table;width:100%;border-top:1px solid #edeef0;padding-top:5px"> <div style="display:table-cell;vertical-align:middle;padding-right:6px"><img src="cid:part3.02020802.00090004@slcoding.com" name="msg-f:1500863175665744936_msg-f:1500858319503376548_compose-unknown-contact.jpg" height="25px" width="25px"></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle;width:100%">
<a href="mailto:paul.j.smith0@gmail.com" style="color:#737f92!important;padding-right:6px;font-weight:bold;text-decoration:none!important" target="_blank">Paul Smith</a></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle">
<font color="#9FA2A5"><span style="padding-left:6px">9 May 2015 20:03</span></font></div></div></div>
<div style="color:#888888;margin-left:24px;margin-right:24px"><div>On Sat, May 9, 2015 at
11:37 AM, Dennis Jacobfeuerborn</div><div><br>I am not an expert
but I believe that most browsers only make between<br>4 to 6
simultaneous connections to a domain. So the first round of<br>requests
are sent and the response received and then the second round<br>go out
and are received back and so forth. Doing a search for<br>something like
"max downloads per domain" may bring you better<br>information.<br><br>Paul<br><br>_______________________________________________<br>nginx
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<div style="margin:30px 25px 10px 25px"><div style="display:table;width:100%;border-top:1px solid #edeef0;padding-top:5px"> <div style="display:table-cell;vertical-align:middle;padding-right:6px"><img src="cid:part3.02020802.00090004@slcoding.com" name="msg-f:1500863175665744936_msg-f:1500858319503376548_compose-unknown-contact.jpg" height="25px" width="25px"></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle;width:100%">
<a href="mailto:dennisml@conversis.de" style="color:#737f92!important;padding-right:6px;font-weight:bold;text-decoration:none!important" target="_blank">Dennis Jacobfeuerborn</a></div> <div style="display:table-cell;white-space:nowrap;vertical-align:middle">
<font color="#9FA2A5"><span style="padding-left:6px">9 May 2015 19:37</span></font></div></div></div>
<div style="color:#888888;margin-left:24px;margin-right:24px"><div>Hi,<br>I'm trying to find
out how to effectively deliver pages with lots of<br>images on a page.
Attached you see opening a static html page that<br>contains lots of img
tags pointing to static images. Please also note<br>that all images are
cached in the browser (hence the 304 response) so no<br>actual data
needs to be downloaded.<br>All of this is happening on a CentOS 7 system
using nginx 1.6.<br><br>The question I have is why is it that the
responses get increasingly<br>longer? There is nothing else happening on
that server and I also tried<br>various optimizations like keepalive,
multi_accept, epoll,<br>open_file_cache, etc. but nothing seems to get
rid of that "staircase"<br>pattern in the image.<br><br>Does anybody
have an idea what the cause is for this behavior and how to<br>improve
it?<br><br>Regards,<br> Dennis<br></div><div>_______________________________________________<br>nginx
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</blockquote></div>
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