IIS Flash Remoting Request Limit introduced with Coldfusion 9

Question

Hi all

We've just been our Coldfusion servers from Enterprise CF 8.01 to CF 9. They are running Win 2008. We ran into trouble on those servers that provide the Flash remoting back-end for a Flex application we provide.

Once the CF 9 upgrade was complete we noticed that during busy times when many Flex clients were connecting, we appeared to have a hard limit of 25 Flash Remoting Requests running, despite having much higher limits (in fact 150) set in CF Admin.

Initially we thought that this was an issue with the fact that Blaze DS was now bundled with CF 9 (rather than a separate install) so we decided to roll-back the CF 9 installation. This, unfortunately, didn't work and we were still stuck with out hard limit of 25 Flash Remoting requests.

Then looking at IIS we noticed that the CF9 ISAPI filter was still installed (after we had ran the Web Service Configuration part of the install). That was removed and the CF 8 one was re-run and all of a sudden the Flash Remoting hard limit disappeared. So it seems that it might have had something to do with the wsconfig of CF 9 (C:\ColdFusion9\runtime\bin\wsconfig.exe)

Has anyone else had this problem, or does anybody know of where these hard limits are configured in IIS?

Any and all help appreciated!

Answer 1

The fact that things reverted to working as expected when you switched the web server configuration would point to that, rather than CF Admin settings themselves, as the smoking gun.

So in fact, if you look closely at the values you changed in IIS when modifying the wildcard mapping, you will notice that each pointed to a directory inside the CF installation, such as [cfroot]\runtime\lib\wsconfig\n (where n is a number representing a directory name CF created when you connected the server to the site using wsconfig, or at installation).

In that directory, you will find jrun_iis6_wildcard.ini, and in my CF9 setting, I find this setting:

#maxworkerthreads=25 <number of worker threads created for asynchronous request processing>

The hash/pound SHOULD mean that it's commented out. Still, it's 25 for me on my CF9 config. I don't see the entry at all in my CF8 ini. I suspect it will be the same for you. Can you confirm?

I can confirm that my setting of 25 does NOT sync with my CF Admin setting for max simult requests or max running jrun threads, which is curious (but again, if it's commented out, maybe it shouldn't be expected to be kept in sync).

Anyway, it seems worth a shot for you to uncomment it and make it larger. Perhaps CF9 has a different underlying default value.

I have looked for any reference to this, and so far don't find much. First I find this, from the CF Doc team, who do in fact recommend that you may need to uncomment and increase this number.

No mention of whether the underlying default changed, so I have asked there (but the blogger withholds comments for approval, so interested readers may not see my comment there yet).

I also find mention of it as the very last sentence of the CF9 Performance Brief. Ah, and now I see that it came up in the Adobe forums as well. Definitely something that people should be made more aware of. I'll certainly blog about it, to add to the spreading of the news, though I'd like to see what the CF doc blog writer says in reply to my comments.

Anyway, let us know if upping this value solves it for you.