Xcode 6 + iOS 7.1 sim slowness?

SquareTheBase · January 6, 2015, 7:37pm

Just moved into Xcode6 with Appium 1.3.4 - its very slow with iOS sim 7.1.

Switched back to Xcode5 using the same Appium and its fast again.

Am I missing something with the Appium setup?

tmysko · January 14, 2015, 10:04am

The same situation here.
The test are running slowly on native part.
Performance reductions is about 2 times.

Lets hope it will be fixed for IOS 8.2

SquareTheBase · February 24, 2015, 10:26pm

Has anyone found a workaround to getting iOS7.1 simulators to not be slow when using XCode6?

vicwomg · February 24, 2015, 10:50pm

Our current workaround is to maintain different versions of Xcode. We install them under /Applications/ using a version suffix (ex. “Xcode-5.1.app”) and switch between them using a script (see below) before relevant CI jobs. Unfortunately, I do not know of a better way.

#switchXcode.sh 
version=""

if [ ! -z $1 ] ; then 
  version="-$1"
fi

cmd="sudo xcode-select -switch /Applications/Xcode$version.app/"
echo $cmd
$cmd

SquareTheBase · February 24, 2015, 11:16pm

Thanks - but we dont support building our app with Xcode5 so I can’t switch the compiler. I need to be able to run iOS7 simulators from XCode6.

I assume your response means that you also see the delay in iOS7 with Xcode6? This seems like an instruments delay issue that the Appium folks fixed for us a while back.

vicwomg · February 24, 2015, 11:46pm

We build and compile our app in Xcode 6 and it runs in the Xcode 5 simulator when we switch back for appium tests, so if you haven’t tried it yet it’s worth a shot.

And yes, I see the same delay. In fact, I am the original poster of this issue

maxmohash · October 9, 2015, 8:37pm

Facing same issue with XCode 7 and iOS 9 Sims now. This is due to facebook instruments-without-delay not supported for XCode 7. I am not sure if they will continue to support this as they have this --> https://github.com/facebook/FBSimulatorControl now which I think they use for their tests.

Check the issues list here --> https://github.com/facebook/instruments-without-delay/issues

I am not sure about workaround that works currently and reliably.

vicwomg · October 9, 2015, 9:06pm

Folks, looks like there’s an active pull request for the fix for this, but fb is disowning instruments-without-delay and recommending that someone just forks the project. I have tried the fix and it works, but it’s a bit hairy since new permissions issues in Xcode 7 require some plist editing to work.

Source:

I took notes of my steps to implement it the fix:


cd ~
git clone https://github.com/lawrencelomax/instruments-without-delay.git
cd instruments-without-delay/
git checkout xcode7-quirks
./build.sh

Next, you’re going to want to edit the plist file at:
/Applications/Xcode-7.0.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/Developer/Library/LaunchDaemons/com.apple.instruments.deviceservice.plist

And replace it with the one from the url below. Be sure to replace the paths ("/Users/lawrencelomax/src") with your own build dirs:

gist.github.com

https://gist.github.com/lawrencelomax/03da6538a0cce1b60c47/

Instructions.md

instruments-without-delay uses the ```DYLD_INSERT_LIBRARIES``` environment variable to shim from the instruments command line all the way down to ```ScriptAgentShim``` which is the iOS Simulator service responsible for interfacing UIAutomation JavaScript with the native ```UIAutomation.framework```. It uses a stack of shims, starting at the ```instruments``` executable, going through ```Simulator.app```. It is an essential part of ios-driver as it removes a pesky 200ms delay that drastically slows down the process of executing end-to-end tests. This is a fixed cost that would occur on every command.

Other than a few things being moved around and renamed in Xcode 7, there is the new issue of the codesigning of the Simulator app that triggers ```amfid``` whenever an unsigned image is loaded. This essentially means that we can't use ```DYLD_INSERT_LIBRARIES``` on the Simulator Process with ```SimShim```

It is however, possible to inject these environment variables at the launchdaemon level. There is a plist for ```DTServiceHub``` at: ```/Applications/Xcode-beta.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/Developer/Library/LaunchDaemons/com.apple.instruments.deviceservice.plist```

It can be modified to inject the ```DTMobileISShim``` (see the attached plist). However, this is less than ideal as this requires modifying the Xcode binary.

com.apple.instruments.deviceservice.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>EnableTransactions</key>
	<true/>
	<key>EnvironmentVariables</key>
	<dict>
		<key>DYLD_INSERT_LIBRARIES</key>
		<string>/Users/lawrencelomax/src/instruments-without-delay/build/DTMobileISShim.dylib</string>

This file has been truncated. show original

DexRobinson · October 14, 2015, 6:02pm

Thank you for these steps. I was able to remove the delay in my scripts. After about 2 weeks of this slowness I was going out of my mind.

alangithubtrader · October 15, 2015, 9:19pm

@vicwomg,

Thank you so much for sharing this with us.

I am giving this a go as I usually run my tests on an actual device.

Any idea if this sort of optimization can be apply to an actual iOS device in the future?

Best Regards,
Alan

alangithubtrader · October 22, 2015, 10:35pm

Thank you very much for sharing this. This works for me and now my tests are running 3X faster.

lillian_ymw · December 22, 2015, 10:48pm

can I say you are my life saver!!! thank yo so much!!!

appiumfan · January 22, 2016, 10:03am

Hi, did you try on simulator only or it’s benefit to both simulator and iOS devices? Thanks

alangithubtrader · January 22, 2016, 11:02pm

Simulator only.

Anyone else got this working with no delay on a device? I am always wondering.

jitendra_l · January 30, 2016, 6:57am

My test cases are executing very slow in simulator after updating xcode…

Simulator : 9.2
Xcode : 7.2
OS X EI Capitan

Can any one help me on this??

jitendra_l · January 30, 2016, 6:58am

@alangithubtrader
Is it working for you on simulator ?

alangithubtrader · February 1, 2016, 6:08pm

Please refer to this link i recently posted.

Jitu1888 · October 26, 2016, 3:04pm

safe.log (1.6 MB)

Jitu1888 · October 26, 2016, 3:05pm

Need a urgent help . I am not able to run the scripts on real device

pawankums · May 9, 2017, 7:07pm

How to do it for Xcode 8+ ?