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wilik
271 post(s)
#03-Dec-15 15:27

I'm Having another web site problem. My maps are served by IIS and consist of bike trail lines overplayed on aerial photographs. When the site loads it frequently hangs and leaves the map image and one or more tool icons replaced with a small x box. Occasionally the tool icon may have the description printed along side, or in place of the tool. Left clicking on the small x box will usually bring in the rest of the map, although frequently with the image off center. No changes have been made to the site or system beyond normal system updates. This behavoir is so bizarre I don't know exactly how to troubleshoot it. Does anyone have any suggestions about how or where to begin? Thanks for any help you might offer

Gustavo Palminha

1,010 post(s)
#06-Dec-15 01:39

Is your website public? Url?

This happened only with that site and / or only with a IIS IMS site?

What IIS version are you using?

I suspect your mention the red X that showup when it's not loaded properly or at all. So did you try to check any windows events at control panels administrator section? Is your internet connection stable? (check it)


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wilik
271 post(s)
#07-Dec-15 00:28

Sorry for the delay.

* Is your website public? Url?

Yes. wa-assoc.com and check out bike trials

* This happened only with that site and / or only with a IIS IMS site?

Just got done with prelim eval of Abyss with out same events. I take it back. It just did the same thing on Abyss

* What IIS version are you using?

v 11.0.25

* So did you try to check any windows events at control panels administrator section?

I haven't seen any events associated with this problem as far as I can determine

* Is your internet connection stable? (check it)

I think it is but don't know what test you would rely on for this.

THANKS FOR THE RESPONSE!

jkelly


1,234 post(s)
#08-Dec-15 22:55

I had a quick look. A couple of things stick out.

You are loading a decent size image (800x600). On my machine, this took 3.5s for 945 KB. That is quite slow, I tested a similar sized image on from a website I run (hosted in the U.S) on my machine and it took < 0.5s. You are also using png format, if you switch that to jpg, this should load a lot faster (at the sacrifice of some image quality, particularly for vectors).

While I don't think the above is the root cause, it will give users a better experience as waiting for seconds for a map to load is not ideal.

My gut feel is that your internet connection is not stable, or is slow. Do you know the speed of your connection? Does anything else get hosted on that same connection? Did you change your provider / plan around the time that these issues started to happen?


James Kelly

http://www.locationsolve.com

cartomatic

884 post(s)
#09-Dec-15 07:52

one more idea - IIS on non-server versions of Windows used to have hard limits of concurrent connections - 10 if i remember well.


maps made easy - www.cartomatic.pl || www.cartoninjas.net

wilik
271 post(s)
#09-Dec-15 17:34

I believe that my current limit of concurrent connections is set at 10. It's hard to imagine 10 concurrent users so I think it's probably ok. Thanks for the comment

wilik
271 post(s)
#09-Dec-15 17:51

I think the root cause may well be related to a timing issue but don't know where it might be. Your image size comment may help - I will check. Most of the pages are overlayed on a virtual aerial photo image which might be slower than ecw or other formats. I do this to be able to get the resolution I want as page is zoomed. I didn't have this issue 1 - 2 years ago when, excluding updates and such, everything was the same.

I didn't want to say this earlier but it seems like the loading of the site has a time limit set someplace. The site will load the map form but will not load some of the icon images , or the map itself. Then, if the map, or icon, is left clicked on it will usually finish loading. But frequently after this is completed the map will be presented off center and it is necessary to click the "size and center" icon. ??

My provider is Comcast, the only reasonable one to pick from in my area. Test speeds are: down - 88 mbps; up - 6 mbps. Still haven't identified how to test stability.

Appreciate you time and help!

cartomatic

884 post(s)
#10-Dec-15 07:37

if you're on a non-server windows, 10 is not a limit of users in IIS but concurrent requests. Browsers are capable of requesting many resources concurrently. If you have limits, some of them will not be processed and may timeout. It's been a known issue for IMS apps deployed under 'normal' windows.

James mentioned the format of the image. jpeg an be 25% of the size of png and will be served quicker - this will yield better user experience but also make more time on the server for the other requests.


maps made easy - www.cartomatic.pl || www.cartoninjas.net

wilik
271 post(s)
#10-Dec-15 22:10

I think I understand the issue of concurrent requests. I can't imagine 10 people trying to get on my site at one time. It turns out the only png images on my site are the tool icon images supplied by Manifold. They are very small and I don't if that is the issue. Thanks and keep the suggestions coming and I will get there eventually.

Gustavo Palminha

1,010 post(s)
#11-Dec-15 17:23

I've testes some of the maps like this one http://wa-assoc.com/BFTrail/default.aspx

I assume you are using VE manifold image server.

While zooming in your raster didn't refresh so I find that strange.

I also experienced slow rendering rates as reported.

Hope it helps.


Stay connected:

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Other >> http://www.spatialmentor.com

wilik
271 post(s)
#12-Dec-15 14:22

Thanks for checking

Yes I am using VE manifold image server. I have been messing with the site so it would have been slower if you saw in prior to preloading. Your observation about the refresh has been a concern for a long time. If the site is preloaded without a lot of hits it will refresh but will stall if you continue to try refreshing. Acts like there is a lack of cache or something like that.

Another thing that might provide a clue is that frequently when it loads it will load everything but the actual map. When that happens the map is replaced by a small icon of a torn document along with the text "submit query". If you click on the text the map will load but be off centered. If you then recenter it everything seems to be ok. Is it possible that the application pool could play into this? I think these maps were made over a period of time when ASP.NET evolved from v2.0 to v4.0. I am running them under v4.0 assuming that they are downward compatible.

Thanks again everybody

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