The Internet Computer (IC), a distributed operating system, is redefining how we build and run web applications. A key feature of IC is "orthogonal persistence" - an innovation that enables applications to process data and state as if they were running in a single environment without explicit file storage and management.

What is Orthogonal Persistence?

In the traditional computing model, the state of a program usually needs to be stored in a disk file through explicit operations, or rely on external storage systems such as databases. Orthogonal persistence is a "transparent persistence" model that allows programs to automatically handle data persistence without explicitly saving the state. The system automatically manages the data and state in memory to ensure that the application can continue to run, and even maintain its execution state when the program crashes or restarts.

How do ICs achieve orthogonal persistence?

IC uses the Actor Model to manage concurrent computing. All programs running on IC are "actors", and each actor has its own independent state. Orthogonal persistence solves the problem of how to efficiently manage large-scale data by dividing the actor's state into "snapshots" and a page-based incremental update mechanism. Each time the system executes a message, it automatically tracks which memory pages have changed and persists these changes in an incremental manner.

Specifically, when an actor processes a message, the IC automatically identifies and records "dirty pages" (i.e., modified memory pages). This incremental update method makes the storage and recovery process more efficient and avoids the huge memory copy overhead that may occur in traditional methods.

IC's persistence advantage

1. Seamless upgrade and fault tolerance: Orthogonal persistence not only ensures the continuity of program status, but also seamlessly supports program upgrades and repairs. In traditional systems, program upgrades often require additional work to ensure that the status is not lost, while the design of IC makes state persistence and upgrades transparent and seamless.

2. Resource optimization: Through incremental snapshots and effective management of memory pages, IC can significantly reduce storage pressure. Compared with copying the entire memory space, the combination of incremental updates and snapshots not only reduces storage requirements, but also improves the efficiency of data recovery.

3. Improve development experience: Developers do not need to pay attention to the underlying persistence details, but can focus on the development of logic and functions. IC's orthogonal persistence allows developers to easily manage the persistence of program states like writing ordinary programs.

Conclusion

Orthogonal persistence brings great convenience to developers. Its transparency and efficiency make IC an ideal platform for building decentralized applications. Through this innovative persistence mechanism, Internet Computer is leading the development of the next generation of Web technology and promoting decentralization and distributed computing to new heights.