Add auto-config explaination to Collector

collector/README.md

@@ -90,68 +90,26 @@ from an S3 object using a CloudFormation template:
 
 Loading configuration from S3 will require that the IAM role attached to your function includes read access to the relevant bucket.
 
+## Auto-Configuration
+
+Configuring the Lambda Collector without the decouple processor and batch processor can lead to performance issues. So the OpenTelemetry Lambda Layer automatically adds the decouple processor to the end of the chain if the batch processor is used and the decouple processor is not.
+
 # Improving Lambda responses times
 At the end of a lambda function's execution, the OpenTelemetry client libraries will flush any pending spans/metrics/logs
-to the collector before returning control to the Lambda environment. The collector's pipelines are synchronous and this 
-means that the response of the lambda function is delayed until the data has been exported. 
+to the collector before returning control to the Lambda environment. The collector's pipelines are synchronous and this
+means that the response of the lambda function is delayed until the data has been exported.
 This delay can potentially be for hundreds of milliseconds.
 
-To overcome this problem the [decouple](./processor/decoupleprocessor/README.md) processor can be used to separate the 
-two ends of the collectors pipeline and allow the lambda function to complete while ensuring that any data is exported 
+To overcome this problem the [decouple](./processor/decoupleprocessor/README.md) processor can be used to separate the
+two ends of the collectors pipeline and allow the lambda function to complete while ensuring that any data is exported
 before the Lambda environment is frozen.
 
-Below is a sample configuration that uses the decouple processor:
-```yaml
-receivers:
-  otlp:
-    protocols:
-      grpc:
-
-exporters:
-  logging:
-    loglevel: debug
-  otlp:
-    endpoint: { backend endpoint }
-
-processors:
-  decouple:
-
-service:
-  pipelines:
-    traces:
-      receivers: [otlp]
-      processors: [decouple]
-      exporters: [logging, otlp]
-```
+See the section regarding auto-configuration above. You don't need to manually add the decouple processor to your configuration.
 
 ## Reducing Lambda runtime
-If your lambda function is invoked frequently it is also possible to pair the decouple processor with the batch 
-processor to reduce total lambda execution time at the expense of delaying the export of OpenTelemetry data. 
+If your lambda function is invoked frequently it is also possible to pair the decouple processor with the batch
+processor to reduce total lambda execution time at the expense of delaying the export of OpenTelemetry data.
 When used with the batch processor the decouple processor must be the last processor in the pipeline to ensure that data
 is successfully exported before the lambda environment is frozen.
 
-An example use of the batch and decouple processors:
-```yaml
-receivers:
-  otlp:
-    protocols:
-      grpc:
-
-exporters:
-  logging:
-    loglevel: debug
-  otlp:
-    endpoint: { backend endpoint }
-
-processors:
-  decouple:
-  batch:
-    timeout: 5m
-
-service:
-  pipelines:
-    traces:
-      receivers: [otlp]
-      processors: [batch, decouple]
-      exporters: [logging, otlp]
-```
+As stated previously in the auto-configuration section, the OpenTelemetry Lambda Layer will automatically add the decouple processor to the end of the processors if the batch is used and the decouple processor is not. The result will be the same whether you configure it manually or not.