无法后台工作，切后台几秒后异常退出

库乐队开启在后台运行功能，但是切到后台几秒钟就会异常退出。

该问题只有在ipad pro10.5上，我的iPhone 11没问题。

我尝试了升级beta版系统，问题依然存在。

下面是出错的log

关键信息是cpu_resource_fatal，cpu占用异常了。

请尽快解决这个问题，谢谢。

{"app_name":"MobileGarageBand","timestamp":"2020-05-10 21:18:55.00 +0800","app_version":"2.3.8","slice_uuid":"8FE55BAE-0F1B-3AF0-A163-F23E8317BDEF","adam_id":408709785,"build_version":"4975.58","bundleID":"com.apple.mobilegarageband","share_with_app_devs":1,"is_first_party":0,"bug_type":"206","os_version":"iPhone OS 13.5 (17F5065a)","incident_id":"1D72FC4E-1BCE-4564-AC48-0B33468C8162","name":"MobileGarageBand"}

Date/Time: 2020-05-10 21:18:41 +0800

End time: 2020-05-10 21:18:55 +0800

OS Version: iPhone OS 13.5 (Build 17F5065a)

Architecture: arm64

Report Version: 29

Incident Identifier: 1D72FC4E-1BCE-4564-AC48-0B33468C8162

Data Source: Microstackshots

Shared Cache: 0x2eea4000 76144FC5-0F16-33CE-AE98-1BE18985BEC0

Command: MobileGarageBand

Path: /private/var/containers/Bundle/Application/0241D20B-DA69-4839-AF7C-29C2CF7C61C1/MobileGarageBand.app/MobileGarageBand

Identifier: com.apple.mobilegarageband

Version: 2.3.8 (4975.58)

Beta Identifier: C2F53F99-DA4C-4888-97D8-9745E577DD26

PID: 553

Event: cpu usage

Action taken: Process killed

CPU: 9 seconds cpu time over 14 seconds (66% cpu average), exceeding limit of 60% cpu over 15 seconds

CPU limit: 9s

Limit duration: 15s

CPU used: 9s

CPU duration: 14s

Duration: 13.65s

Duration Sampled: 4.14s

Steps: 7

Hardware model: iPad7,3

Active cpus: 3

Heaviest stack for the target process:

7 ??? (libsystem_pthread.dylib + 44440) [0x1af051d98]

7 ??? (MobileGarageBand + 16043460) [0x101334dc4]

3 ??? (libsystem_kernel.dylib + 13688) [0x1af10e578]

Powerstats for: MobileGarageBand [553]

Bundle ID: com.apple.mobilegarageband

Adam ID: 408709785

Is first party: No

App version: 2.3.8

Build version: 4975.58

Is Beta: No

Share with Devs: Yes

UUID: 8FE55BAE-0F1B-3AF0-A163-F23E8317BDEF

Path: /private/var/containers/Bundle/Application/0241D20B-DA69-4839-AF7C-29C2CF7C61C1/MobileGarageBand.app/MobileGarageBand

Architecture: arm64

Footprint: 85.22 MB

Start time: 2020-05-10 21:18:50 +0800

End time: 2020-05-10 21:18:54 +0800

Num samples: 7 (100%)

CPU Time: 2.731s

Primary state: 7 samples Non-Frontmost App, Non-Suppressed, User mode, Effective Thread QoS Default, Requested Thread QoS Default, Override Thread QoS Unspecified

User Activity: 0 samples Idle, 7 samples Active

Power Source: 7 samples on Battery, 0 samples on AC

7 ??? (libsystem_pthread.dylib + 44440) [0x1af051d98]

7 ??? (MobileGarageBand + 16043460) [0x101334dc4]

3 ??? (libsystem_kernel.dylib + 13688) [0x1af10e578]

3 ??? (MobileGarageBand + 16043948) [0x101334fac]

1 ??? (libsystem_kernel.dylib + 13660) [0x1af10e55c]

Binary Images:

0x1003e8000 - ??? com.apple.mobilegarageband 2.3.8 (4975.58) <8FE55BAE-0F1B-3AF0-A163-F23E8317BDEF> /private/var/containers/Bundle/Application/0241D20B-DA69-4839-AF7C-29C2CF7C61C1/MobileGarageBand.app/MobileGarageBand

0x1af047000 - 0x1af057fff libsystem_pthread.dylib <071D150C-3808-3BEB-8CA8-EF5E38F36128> /usr/lib/system/libsystem_pthread.dylib

0x1af10b000 - 0x1af139fff libsystem_kernel.dylib <27878723-0BCB-378F-8733-93D0030863CB> /usr/lib/system/libsystem_kernel.dylib