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Topic: Images not displaying or unable to load ?

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Subject: Images not displaying or unable to load ?
Date Posted: 2/23/2015 12:48 AM ET
Member Since: 8/20/2007
Posts: 1,020
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For several days I've been noticing errors with the site not displaying images correctly and wondering if others are also seeing this.

There are two cases. In the first case, when going to a book's detail page, the title shows up in narrow box just large enough to fit the text where the image should be. In the second case, when clicking on the box or image on the details page I get a pop-up that says "This image could not be loaded".

In both cases, the images will appear either after redisplaying the page or clicking on the image again, or after refreshing my browser with Ctrl-F5, but  sometimes it takes more than one try before the images display. Note that the keystroke Ctrl-F5 to refresh one's browser works on Firefox, but I'm not certain if this is the same for Chrome, Safari, or other browsers.

Date Posted: 2/23/2015 2:06 AM ET
Member Since: 8/23/2009
Posts: 4,581
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I noticed this the other day (I think yesterday morning) in internet explorer and had to go to chrome but didn't have the problem there.  I just though it was a glitch related to pbs not being fully compatible with internet explorer which happens some times.  I prefer internet explorer and I notice that I have problems like this from time to time.  If its happening in others browsers it can't be an IE glitch from incompatibility.

Last Edited on: 2/23/15 2:06 AM ET - Total times edited: 1
Cathy A. (Cathy) - ,
Date Posted: 2/23/2015 9:40 AM ET
Member Since: 12/27/2005
Posts: 4,150
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That sounds like a problem with an Akamai Edge server (where the static files are cached) getting timeouts or network problems when it tries to reach back to the paperbackswap.com server for the files it doesn't have.

The title layout problem would be due to a css file not being on the cache server yet, and the image loading problem would be due to the image itself not being there. When your browser asks for these files from the cache server, the cache server goes and asks for them from the paperbackswap server. Then before it hands them off to you, it saves them so it can fulfill the next request without having to ask again. This reduces load on the paperbackswap servers and makes the site run faster since the cache servers are closer to the users. If the primary server doesn't respond in time, then you get the layout problems you're seeing. By the time you've pressed F5, the file has made it to the cache server and is then sent to you, so the problem clears up.

It's also possible that the files are there on the cache server, but it's having trouble serving them in a timely fashion. I haven't seen these problems myself, so it's possible that the cache server in your area is misbehaving while the one in my area is working better.

Date Posted: 2/23/2015 4:18 PM ET
Member Since: 8/20/2007
Posts: 1,020
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Thanks for the explanation, Cathy.

Also, regarding browsers, I use Firefox and did not try Chrome in this case to see if there was any difference between them. I don't use IE.

I know that cache servers store images for faster retrieval without having to negotiate with the paperbackswap server, and this generally works well. The problem described in my original post has occurred occasionally in the past, but this week I have been seeing a lot more of this behavior than usual. I wasn't sure if this is an issue with my "local" cache server or my browser, or if there is a more general problem that others are also seeing.

I am in the book image group on PBS and also do a lot of image approving. In addition, I am frequently checking listings to be sure that new images install and update correctly, so I probably look at more book listings and images than most other members.