@Degard Here are the steps that I did:
1. Checkout this project: https://github.com/lawrencelomax/instruments-without-delay first. Make sure you can open it by Xcode and build it successfully.
Back up this file: ./Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/Developer/Library/LaunchDaemons/com.apple.instruments.deviceservice.plist ( I assume your Xcode is installed in the same directory of mine, otherwise you can do a search from Xcode directory with file name "com.apple.instruments.deviceservice.plist")
Open that file and add this key - dict:
<key>EnvironmentVariables</key>
<dict>
<key>DYLD_INSERT_LIBRARIES</key>
<string>/Users/tbao/Developer/tools/appium/instruments-without-delay/build/DTMobileISShim.dylib</string>
<key>LIB_PATH</key>
<string>/Users/tbao/Developer/tools/appium/instruments-without-delay/build</string
</dict>
Note: You have to change the values for the two keys DYLD_INSERT_LIBRARIES, LIB_PATH according to your checked out instruments-without-delay project.
Now try to run appium again and see if it works. To be frankly, how the author of this project solves the problem is still a mystery to me but at least it works for me. Let me know if you have any problem and I'll try to get back to you when I have time