Devicelab microbenchmarks failures #19096
Description
Since the last engine roll the devicelab microbenchmarks are failing due to an exception parsing the JSON response, and the completeError call failing claiming it was already completed (!). I added some debug logging in #19093 which I'm reverting. Below is some example output for further investigation. I still can't see how it's already completed, but at least we have the JSON decoding exception (I'm not yet sure if the JSON has been put in the string twice, or that's just multiple output lines, in which case it's even more strange).
[ +2 ms] /Volumes/DevicelabAndroid/sdk/platform-tools/adb version
[ +15 ms] Android Debug Bridge version 1.0.39
Version 0.0.1-4500957
Installed as /Volumes/DevicelabAndroid/sdk/platform-tools/adb
[ ] /Volumes/DevicelabAndroid/sdk/platform-tools/adb start-server
[ +14 ms] Installing build/app/outputs/apk/app.apk...
[ ] /Volumes/DevicelabAndroid/sdk/platform-tools/adb -s ZY2245H6ZS install -t -r build/app/outputs/apk/app.apk
[+8928 ms] Success
[ +1 ms] /Volumes/DevicelabAndroid/sdk/platform-tools/adb -s ZY2245H6ZS shell echo -n c953ffd01afebc6430031a30781d38fc7329b423 > /data/local/tmp/sky.com.yourcompany.microbenchmarks.sha1
[ +60 ms] Moto G 4 startApp
[ +3 ms] /Volumes/DevicelabAndroid/sdk/platform-tools/adb -s ZY2245H6ZS shell am start -a android.intent.action.RUN -f 0x20000000 --ez enable-background-compilation true --ez enable-dart-profiling true com.yourcompany.microbenchmarks/io.flutter.app.FlutterActivity
[ +935 ms] Starting: Intent { act=android.intent.action.RUN flg=0x20000000 cmp=com.yourcompany.microbenchmarks/io.flutter.app.FlutterActivity (has extras) }
[ ] Waiting for observatory port to be available...
[+53878 ms] I/flutter ( 7569): ================ RESULTS ================
[ ] I/flutter ( 7569): :::JSON::: {"stock_build_iteration":7099.030288689068}
[ ] I/flutter ( 7569): ================ FORMATTED ==============
[DEBUG:DANTUP] Completing successfully
[DEBUG:DANTUP] Decoding JSON failed (FormatException: Unexpected character (at line 2, character 2)
{"stock_build_iteration":7099.030288689068}
^
). JSON string was: {"stock_layout_iteration":3821.4360672440143}
{"stock_build_iteration":7099.030288689068}
Task failed: Bad state: Future already completed
Stack trace:
dart:async _Completer.completeError
package:flutter_devicelab/tasks/microbenchmarks.dart 136:19 _readJsonResults.
===== asynchronous gap ===========================
dart:async _BoundSinkStream.listen
package:flutter_devicelab/tasks/microbenchmarks.dart 116:8 _readJsonResults
package:flutter_devicelab/tasks/microbenchmarks.dart 53:22 createMicrobenchmarkTask.._runMicrobench._run
===== asynchronous gap ===========================
dart:async _asyncThenWrapperHelper
package:flutter_devicelab/tasks/microbenchmarks.dart 27:48 createMicrobenchmarkTask.._runMicrobench._run
package:flutter_devicelab/tasks/microbenchmarks.dart 55:18 createMicrobenchmarkTask.._runMicrobench
===== asynchronous gap ===========================
dart:async _asyncThenWrapperHelper
package:flutter_devicelab/tasks/microbenchmarks.dart 22:19 createMicrobenchmarkTask.
package:flutter_devicelab/framework/framework.dart 125:36 _TaskRunner._performTask.
[ ] I/flutter ( 7569): Stock build: 7099.0 µs per iteration
[+18033 ms] I/flutter ( 7569): ================ RESULTS ================
[ ] I/flutter ( 7569): :::JSON::: {"stock_build_iteration":7099.030288689068}
[ ] I/flutter ( 7569): ================ FORMATTED ==============
[DEBUG:DANTUP] Completing successfully
[DEBUG:DANTUP] (done)
[ ] I/flutter ( 7569): Stock build: 7099.0 µs per iteration