ArcGIS Web Adaptor 10.1 for IIS causing some tiles to load really slow

[SergeyBayshev1]

Hi!
I've ran into a performance issue when using ArcGIS Web Adaptor 10.1 for IIS. Web Adaptor For IIS 10.1 and ArcGIS for Server 10.1 are separate servers. Some tiles on a couple of specific scales are constantly downloading really slow if they are requested via Web Adaptor(port 80). The tiles may be different but the scales are always the same. Other scales and tiles are downloading rapidly. If I am requesting the same tiles from my Web Adaptor Server via ArcGIS Server (port 6080) - every tile downloads fast.

Before I realized that it is possibly an issue of the Web Adaptor I tried restaring all the services and servers, recreating tile cache, deleteing the map service and creating a new one with the same name. Nothing helped. But when I create the same service with the same settings and another name everything works fine. If I am requesting the tiles from
After that I've reinstalled the Web Adaptor but it didn't help either.

What else should I try?


2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1278/2475 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 13166
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1279/2474 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 13166
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1278/2476 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 13135
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1278/2479 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 11996
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1281/2475 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 140
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1280/2477 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 140
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1278/2479 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 156
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1279/2477 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 171
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1280/2476 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 234
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1281/2478 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 140
2013-05-13 05:04:37 10.127.0.248 GET /MapServer/tile/3/1279/2479 - 80 - 31.172.195.207 Opera/9.80+(Windows+NT+5.1)+Presto/2.12.388+Version/12.15 200 0 0 12901

[BrianRassier]

Hello -

We are seeing some similar issues, and we're also wondering if it's related to the Web Adaptor.  Did you ever find more insight into your problem?

Thanks
-Brian

[WilliamCraft]

If you are seeing the tiles download fast when logged into the Web Adaptor server and making the requests directly from that machine, but they are consistently slow to download from everywhere else, it sounds like there could be an issue with network connectivity to and from that server and possibly for the network as a whole.  You should also test throughput to/from that server to make sure that a bad network card isn't in play here.  Even though the tile downloads are extremely slow for specific tiles, do they still download eventually or is it the case that some never download at all?  Can you run Fiddler in the background when making the requests from client PC to see if you can collect more information?

[BrianRassier]

Hello -

Thanks for your reply.  We did run some tracing on the client and server.  The pattern we're seeing is that the request gets to IIS fairly quickly, then IIS takes 2-7 seconds to serve the tile.  We have fiddler running on the ArcGIS Server too, which shows the web adapter request to ArcGIS Server, and the tile fetching as a whole is very quick.  So there's something in IIS that is a sticking point, which could be related to the web adaptor.

This only happens occasionally, maybe 10 minutes out of an hour.  Let me know if this may be related to anything you've seen.

Thanks!
-Brian

[WilliamCraft]

So even through the web adaptor, where you are seeing this issue occur, it only happens 10 minutes out of every hour?  Is something running on the server once per hour for about 10 minutes?  Check your scheduled tasks to see if something is set to run regularly that may be consuming resources on your server (check both servers).  Also, take a look at the processes tab under Task Manager on both machines when the issue occurs... sort despondingly by the memory column so that you can try to isolate any particular process that may be bogging down the server(s).  Is it also possible that you antivirus software, if any, is running a full scan every hour?