My general experience of Serverless across the three major clouds is that:
GCP takes up to two minutes.
AWS takes about a minute.
Azure is a bit random and has bad days when it can take five minutes, but mostly around two minutes.
Some of it rather depends on how you measure it, and what you use to deploy it. Something like Serverless Framework will do ...
This will vary based on your cloud provider and what services you are using. AWS Lambda functions are designed to be highly available for the region. Per the AWS Lambda FAQ:
When you update a Lambda function, there will be a brief window of time, typically less than a minute, when requests could be served by either the old or the new version of your ...
According to this GitHub readme
OpenWhisk is a serverless event-based programming service.
In order to get an idea how to setup this tool on a cluster one could run the following code that is defined in the readme:
# Clone openwhisk
git clone --depth=1 https://github.com/apache/incubator-openwhisk.git openwhisk
# Change directory to tools/vagrant