Performance Hosting under WAS vs Host as Service?

Question

I have some performance issue when I host WCF service (net.tcp) under WAS (Windows Activation Services IIS 7). It is working fine if I host service as a console application.

The issue is WCF Become Slow After Being Idle For 15 Seconds and a solution. After applying Wenlong Dong workaround the delay is gone if i host service as a console app, but it does not work if I host service in WAS (IIS 7).

I tried to put "ThreadPoolTimeoutWorkaround.DoWorkaround()" in static AppInitialize() as suggested here, still no luck.

Thanks