Crash in DefaultAudioClientObserver#onMetrics

[tmilovan123]

Describe the bug
A fatal crash encountered for one of our customers in production. Opening a tracking issue.

To Reproduce
Happened during AV session at some point during metric emission.

Expected behavior
No crash

Logs
Stacktrace:

java.util.ConcurrentModificationException: null
    at java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:760)
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:793)
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:791)
    at com.amazonaws.services.chime.sdk.meetings.internal.metric.DefaultClientMetricsCollector.maybeEmitMetrics(DefaultClientMetricsCollector.kt:88)
    at com.amazonaws.services.chime.sdk.meetings.internal.metric.DefaultClientMetricsCollector.processAudioClientMetrics(DefaultClientMetricsCollector.kt:31)
    at com.amazonaws.services.chime.sdk.meetings.internal.audio.DefaultAudioClientObserver.onMetrics(DefaultAudioClientObserver.kt:340)

Test environment Info (please complete the following information):

• Device: SM-G991U
• OS: Android 12
• Version amazon-chime-sdk: 0.13.1
• Version amazon-chime-sdk-media: 0.13.1
• Can you reproduce this in the demo app? No

[dingyishen-amazon]

Thank you for reporting. If it cannot be reproduced on demo app, it’d be more efficient to compare the difference of implementation logic between your application and demo app.

[tmilovan123]

It most likely can be reproduced since, as it's evident from the stack trace, DefaultClientMetricsCollector is using a non-thread-safe collections to store in-memory data. Something that can definitely be corrected.

[hokyungh]

Thanks for reporting. As you stated, It does look like it is not thread-safe. Will update the ticket once we have solutions.

[georgezy-amzn]

According to the stacktrace, it happens at DefaultClientMetricsCollector.maybeEmitMetrics(DefaultClientMetricsCollector.kt:88). I checked DefaultClientMetricsCollector for v0.13.1, there is no line 88.
Are you using a custom build?

[tmilovan123]

Hi George,

No, we always used the binaries downloaded from here: https://github.com/aws/amazon-chime-sdk-android/releases

Next release we're updating to 0.15.3 / Maven dependencies.

Thanks,
Tanya

[georgezy-amzn]

Hi @tmilovan123,

Do you still observe the crashes with newer version of SDK?

[ziyiz-amzn]

The fix is released in https://github.com/aws/amazon-chime-sdk-android/releases/tag/v0.17.5