Clarify MetricReader.Collect result

open-telemetry · Apr 18, 2022 · 9bfca9a · 9bfca9a
1 parent a50def3
commit 9bfca9a
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/specification/metrics/sdk.md b/specification/metrics/sdk.md
@@ -710,7 +710,10 @@ Instruments](./api.md#asynchronous-instrument-api) involved, their callback
 functions will be triggered.
 
 `Collect` SHOULD provide a way to let the caller know whether it succeeded,
-failed or timed out.
+failed or timed out. When the `Collect` operation fails or timed out only on
+part of the instruments, like one async instrument callback timed out but others
+succeeded, the SDK SHOULD return all successfully collected result a failed
+reasons list to the caller.
 
 `Collect` does not have any required parameters, however, [OpenTelemetry
 SDK](../overview.md#sdk) authors MAY choose to add parameters (e.g. callback,