add snapstart span#911
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| pub duration_ms: f64, | ||
| } | ||
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| /// Restore report metrics |
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Please add test coverage for new struct and new field above.
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besides the unit tests, can we consider adding tests in bottlecap/tests/ to verify: |
| { | ||
| error!("Failed to send platform restore report to processor: {}", e); | ||
| } | ||
| } |
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Can we log error in case metrics is None as it may indicate malformed data?
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https://datadoghq.atlassian.net/browse/SVLS-7836?atlOrigin=eyJpIjoiMWNmZTMzOGE4NGEwNDE4MTk5Njk0N2ZmMmU3MzExMjgiLCJwIjoiaiJ9 The extension neither creates SnapStart spans nor emits SnapStart metrics. This PR adds both. When a lambda with snapshot enabled is invoked for the first time, we get `Platform.RestoreStart` and `Platform.RestoreReport`. These effectively take the place of `Platform.InitStart` and `Platform.InitReport` events, so our code flow is pretty much identical to how we handle the cold start span and duration metric. Note - When a SnapStart instance is restored, we actually receive the `Platform.InitStart` and `Platform.InitReport` events in addition to the `Platform.RestoreStart` and `Platform.RestoreReport`. However, the `Init` events are not from the sandbox starting for that invoke. These `Init` events are actually generated from when the Snapshot is created. This is very misleading - You can see that this [trace](https://ddserverless.datadoghq.com/serverless/aws/lambda?fromUser=false&graphType=flamegraph&group=&highlight=snapstart-java-cdk-function&panel_end=1761860524106&panel_paused=false&panel_start=1761846124106&shouldShowLegend=true&sp=%5B%7B%22p%22%3A%7B%22entityId%22%3A%22aws-lambda-functions%2Bsnapstart-java-cdk-function%2Bus-east-1%2B425362996713%22%7D%2C%22i%22%3A%22lambda-panel%22%7D%2C%7B%22p%22%3A%7B%22traceID%22%3A%225400520227836710313%22%2C%22selectedSpanID%22%3A%22644948261311059067%22%7D%2C%22i%22%3A%22trace-panel%22%7D%5D&spanID=644948261311059067&text_search=snapstart&traceID=5400520227836710313&traceQuery=&start=1761845683104&end=1761860083104&paused=false) is more than 3 hours long. The lambda was invoked more than 3 hours after the snapshot version was created. (This is the current experience). I deployed my own extension with the changes and confirmed we are now getting a restore span and not an init span, [link](https://ddserverless.datadoghq.com/serverless/aws/lambda?fromUser=false&graphType=flamegraph&group=&panel_end=1761860640000&panel_paused=false&panel_start=1761846240000&shouldShowLegend=true&sp=%5B%7B%22p%22%3A%7B%22entityId%22%3A%22aws-lambda-functions%2Bsnapstart-java-function%2Bus-east-1%2B425362996713%22%7D%2C%22i%22%3A%22lambda-panel%22%7D%2C%7B%22p%22%3A%7B%22traceID%22%3A%226634828896084800457%22%2C%22selectedSpanID%22%3A%222017721198037440020%22%7D%2C%22i%22%3A%22trace-panel%22%7D%5D&spanID=2017721198037440020&text_search=snapstart&traceID=6634828896084800457&traceQuery=&start=1761845683104&end=1761860083104&paused=false).
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Task
https://datadoghq.atlassian.net/browse/SVLS-7836?atlOrigin=eyJpIjoiMWNmZTMzOGE4NGEwNDE4MTk5Njk0N2ZmMmU3MzExMjgiLCJwIjoiaiJ9
Overview
The extension neither creates SnapStart spans nor emits SnapStart metrics. This PR adds both.
When a lambda with snapshot enabled is invoked for the first time, we get
Platform.RestoreStartandPlatform.RestoreReport. These effectively take the place ofPlatform.InitStartandPlatform.InitReportevents, so our code flow is pretty much identical to how we handle the cold start span and duration metric.Note - When a SnapStart instance is restored, we actually receive the
Platform.InitStartandPlatform.InitReportevents in addition to thePlatform.RestoreStartandPlatform.RestoreReport. However, theInitevents are not from the sandbox starting for that invoke. TheseInitevents are actually generated from when the Snapshot is created. This is very misleading - You can see that this trace is more than 3 hours long. The lambda was invoked more than 3 hours after the snapshot version was created. (This is the current experience).Testing
I deployed my own extension with the changes and confirmed we are now getting a restore span and not an init span, link.