Introduction

In this article, I will describe the two generations of Google Cloud Functions (GCF), their features, limitations, and the improvements made in the second generation.

1st Generation

As a serverless compute platform, GCF was launched in 2016 to enable developers to execute code without the need to manage the underlying infrastructure. The first generation of GCF aimed to simplify the process of building and deploying small, single-purpose functions in the cloud.

Features of the 1st Generation

The initial iteration of GCF offered a lightweight, event-driven architecture that allowed developers to focus on writing code while freeing them from the burden of server management. Key features of this generation included:

• Support for Node.js, Python, and Go runtimes, which enabled developers to choose from a variety of languages.
• Automatic scaling based on the number of incoming requests, ensuring efficient resource utilization.
• A pay-per-use pricing model that made GCF cost-effective for various use cases.
• Integration with other Google Cloud services such as Pub/Sub, Storage, and Firestore, simplifying the process of building end-to-end applications.
• HTTP triggers for invoking functions through RESTful APIs, providing a convenient way to expose functionality to external clients.

Limitations and Drawbacks

Despite the numerous advantages of the 1st generation of GCF, there were several limitations and drawbacks that developers had to contend with:

• Limited runtime support, which restricted the choice of programming languages and frameworks.
• Cold start latency, which could result in slow function execution times for infrequently used functions due to the time required to initialize the environment.
• Restricted customizability of the function execution environment, constraining the ability to configure settings or install custom dependencies.
• Limited support for long-running functions, with a maximum execution time of 540 seconds, which made it difficult to use GCF for certain use cases that required longer processing times.

These limitations prompted the need for an improved version of Google Cloud Functions, which materialized in the form of the 2nd generation. This new version aimed to address the shortcomings of its predecessor and provide developers with a more powerful and flexible serverless platform.

The 2nd Generation

In response to the limitations of its predecessor, the second generation of GCF was developed to provide developers with a more robust and feature-rich serverless platform. This new generation introduced significant enhancements to the platform's capabilities and performance, addressing many of the drawbacks of the first generation.

Enhanced Capabilities and Performance

The second generation of GCF came with a host of new features and improvements, including:

• Expanded runtime support, which broadened the choice of programming languages by adding Java, Ruby, PHP, and .NET, allowing developers to work in their preferred language.
• Significantly reduced cold start latency, resulting in faster function execution times and improved responsiveness for users.
• Improved resource allocation, granting developers greater control over CPU and memory resources to optimize their functions' performance.
• Support for long-running functions, increasing the maximum execution time to 900 seconds, which enabled GCF to cater to a wider range of use cases.
• Introduction of VPC (Virtual Private Cloud) connectors, offering enhanced networking options for secure and reliable connections to other services within the Google Cloud ecosystem.

Scaling and Security Improvements

Besides the performance enhancements, the second generation of GCF also focused on providing better scaling and security options for developers:

• Fine-grained scaling controls, allowing developers to customize the number of concurrent executions and the maximum number of instances per function, resulting in more efficient resource utilization and cost management.
• Enhanced security features, including private networking, custom IAM roles, and Secret Manager integration, which improved the overall security posture of GCF-based applications.
• Improved monitoring and observability through the integration of Cloud Monitoring and Cloud Trace, enabling developers to gain valuable insights into their functions' performance and troubleshoot potential issues more effectively.

By addressing many of the limitations and drawbacks of the first generation, the second generation of Google Cloud Functions aimed to provide a more powerful, flexible, and secure serverless platform for developers to build and deploy a wide range of applications. This new generation made it easier for developers to take advantage of the benefits of serverless computing, while also catering to more complex and demanding use cases.

Comparison

Below is a table comparing the 1st and 2nd generations.

Feature	Cloud Functions (1st gen)	Cloud Functions (2nd gen)
Image registry	Container Registry or Artifact Registry	Artifact Registry only
Request timeout	Up to 9 minutes	- Up to 60 minutes for HTTP-triggered functions - Up to 9 minutes for event-triggered functions
Instance size	Up to 8GB RAM with 2 vCPU	Up to 16GiB RAM with 4 vCPU
Concurrency	1 concurrent request per function instance	Up to 1000 concurrent requests per function instance
Traffic splitting	Not supported	Supported
Event types	Direct support for events from 7 sources	Support for any event type supported by Eventarc, including 90+ event sources via Cloud Audit Logs
CloudEvents	Supported only in Ruby, .NET, and PHP runtimes	Supported in all language runtimes

References

https://cloud.google.com/functions/docs/concepts/version-comparison