Hi

I have six website that use web-connect on a Windows 2012 Server Standard iCore 7 3.5GHz 8 gig of ram 500 gig hard drive. The processor hardly ever gets over 10% and the memory runs at about 30%. Each of the web sites has its own application pool. So I usually see 10-12 copies of my COM server in memory since each application pool is configured to run 2 COM servers. The problem is that the performance of the web sites is often quite slow. The web page slowly refreshes in the browser. When I remote into the server using Remote Desktop Top the screen often does not response to mouse clicks in a timely way and I often loose the connection for a second or two and I see the re-connecting dialog.

I use to have all of this on a less powerful Windows 2003 Server with one application pool and it worked just fine. So I changed back to one application pool on the new server and everything went back to working properly.

So my question is why did the application pools cause such problems? The documentation recommends having multiple application pools which should give increased performance but that was not my experience. I am running with Web-Connect 5.41 and would like to understand what happened when I used more than one application pool and saw the performance drop. Should I changed the application pool so only one copy of the COM server is used? Should the number of application pools be tied to the number of cores?

Simon

Hi Simon,

I suspect that's circumstantial evidence and I would suspect something else happening on the server to cause the slow downs. The only way you can really compare this is by taking the apps out of the separate app pools and putting it into a single app pool - I bet anything nothing much would change.

Using separate Application Pools is Ok, but certainly not required - unless you have massively busy applications that overload a single pools limits. But with VFP you usually run into load problems on the VFP/COM front long before you run into IIS issues. So running with multiple pools is not absolutely necessary. Generally I do isolate my apps, but that's mainly so that if something happens to lock up one app, it doesn't take the others with it. It's not for better performance.

Application Pools are simply executable containers - they don't directly affect anything on a machine. They simply isolate applications from each other. But running multiple app pools certainly will cause your memory usage to go up as each AppPool uses about it's own dedicated pool of memory (which tends to be in the 50 meg range for Web Connection only AppPools).

There are lots of things that can affect performance. First and foremost - especially if you're running file based - Anti virus can be crippling. Turn that off temporarily (if you have it) and see if that helps. Slow or near capacity disks can also be a problem. In file mode a full temp folder can cause major problems.

Also are you running on a physical box, or inside a virtual machine? Inside of a VM multiple Application Pools might cause thread starvation if the VM is under-provisioned.

Hope this helps,

+++ Rick ---

I have taken the applications out of the separate AppPools and put them all in one. The server is working much better now than it has in weeks. I am not running file based everything is COM. Only 156 gigabytes out of 549 gigabytes is used on the hard drive. The processor is an iCore 7 quad core 3.6 gHz with 8gig of ram. I will monitor it for a while but this is the best it has run in months.

Simon

Intersting...

I'm not sure I can consolidate that with anything I know about how AppPools work, unless there's some crazy configuration that causes them to interact with each other. Especially since Web Connection barely makes any demands on the AppPool itself since all the processing occurs externally in the EXE servers.

+++ Rick ---