For normal testing I build an application using Xcode and selecting "Build for Profiling" from the Product menu. For production I do "xcodebuild clean build -configuration Release ......." I notice a big performance difference. In my case the XCode profiling build runs in under a minute, the xcodebuild version takes over 4 minutes. The XCode profiling build uses the Release configuration, the xcodebuild is also using the Release configuration. What additional configuration options are being set/used when "Building for Profiling"? I'm having a hard time finding an answer to this question.