Now I have a computer here is the whole thing:

namespace MyProject.Events
{
    using StackExchange.Profiling;
    using Umbraco.Core;

    public class UmbracoEvents : ApplicationEventHandler
    {
        protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            // Set MaxJson size for Miniprofiler
            MiniProfiler.Settings.MaxJsonResponseSize = 104857600;
        }
    }
}

Hi Shannon, looking into it a bit further it might not be an issue specific to Umbraco... I think

Miniprofiler only offers an option to change the MaxJsonResponseSize, (Thanks Jeavon for that snippet) but not the recursion limit which is odd.

What I can't tell is whether the limit is being exceed by something I am doing or by something within Umbraco. There's not enough info in the exception message just now to be sure so I'll probably have to download the source and attach to the process.

It's vital I figure this out anyway as I'm experience some severe slow down on a site we've just deployed to Azure (6x slower), that's with Examine config changes, trimming fcn etc.

Cheers for the input. Appreciate it!

P.S. The version of MiniProfiler that bundles with Umbraco is really old (~2.5 years) and un-upgradeable. Is there a specific reason for this?