低内存测试时Cannot run program "su": error=13, Permission denied崩溃

[baoolong]

在使用低内存测试时，程序崩溃，抓到如下日志
02-10 14:21:12.506 W/System.err( 3692): java.io.IOException: Cannot run program "su": error=13, Permission denied
02-10 14:21:12.508 W/System.err( 3692): at java.lang.ProcessBuilder.start(ProcessBuilder.java:1050)
02-10 14:21:12.508 W/System.err( 3692): at java.lang.Runtime.exec(Runtime.java:695)
02-10 14:21:12.508 W/System.err( 3692): at java.lang.Runtime.exec(Runtime.java:525)
02-10 14:21:12.508 W/System.err( 3692): at java.lang.Runtime.exec(Runtime.java:422)
02-10 14:21:12.508 W/System.err( 3692): at k0.e.b(Unknown Source:24)
02-10 14:21:12.508 W/System.err( 3692): at k0.e.a(Unknown Source:6)
02-10 14:21:12.508 W/System.err( 3692): at com.ayst.stresstest.test.ddr.DDRTestFragment.onCreate(Unknown Source:6)
02-10 14:21:12.508 W/System.err( 3692): at android.app.Fragment.performCreate(Fragment.java:2503)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1256)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.addAddedFragments(FragmentManager.java:2426)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2205)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2161)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2062)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.dispatchMoveToState(FragmentManager.java:3051)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:2998)
02-10 14:21:12.508 W/System.err( 3692): at android.app.FragmentController.dispatchActivityCreated(FragmentController.java:182)
02-10 14:21:12.508 W/System.err( 3692): at android.app.Activity.performCreate(Activity.java:7156)
02-10 14:21:12.508 W/System.err( 3692): at android.app.Activity.performCreate(Activity.java:7140)
02-10 14:21:12.508 W/System.err( 3692): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
02-10 14:21:12.508 W/System.err( 3692): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
02-10 14:21:12.508 W/System.err( 3692): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
02-10 14:21:12.508 W/System.err( 3692): at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
02-10 14:21:12.508 W/System.err( 3692): at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
02-10 14:21:12.508 W/System.err( 3692): at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
02-10 14:21:12.508 W/System.err( 3692): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
02-10 14:21:12.509 W/System.err( 3692): at android.os.Handler.dispatchMessage(Handler.java:106)
02-10 14:21:12.509 W/System.err( 3692): at android.os.Looper.loop(Looper.java:193)
02-10 14:21:12.509 W/System.err( 3692): at android.app.ActivityThread.main(ActivityThread.java:6669)
02-10 14:21:12.509 W/System.err( 3692): at java.lang.reflect.Method.invoke(Native Method)
02-10 14:21:12.509 W/System.err( 3692): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
02-10 14:21:12.509 W/System.err( 3692): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:891)
02-10 14:21:12.509 W/System.err( 3692): Caused by: java.io.IOException: error=13, Permission denied
02-10 14:21:12.509 W/System.err( 3692): at java.lang.UNIXProcess.forkAndExec(Native Method)
02-10 14:21:12.509 W/System.err( 3692): at java.lang.UNIXProcess.(UNIXProcess.java:133)
02-10 14:21:12.510 W/System.err( 3692): at java.lang.ProcessImpl.start(ProcessImpl.java:132)
02-10 14:21:12.510 W/System.err( 3692): at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
02-10 14:21:12.510 W/System.err( 3692): ... 30 more