Serverless set a Lamdba function timeout to 6.00 seconds, If you didn't write timeout statement in serverless.yml.
# serverless.yml
service: myService
provider:
name: aws
runtime: nodejs6.10
memorySize: 512 # optional, in MB, default is 1024
timeout: 10 # optional, in seconds, default is 6
versionFunctions: false # optional, default is true
functions:
hello:
handler: handler.hello # required, handler set in AWS Lambda
name: ${self:provider.stage}-lambdaName # optional, Deployed Lambda name
description: Description of what the lambda function does # optional, Description to publish to AWS
runtime: python2.7 # optional overwrite, default is provider runtime
memorySize: 512 # optional, in MB, default is 1024
timeout: 10 # optional, in seconds, default is 6Reference: serverless/serverless#2640