kvstore-concurrency

Introduction

A multi-threaded, persistent key/value store server and client with synchronous networking over a custom protocol.

Points

• Synchronous networing
• Respond to multiple requests using increasingly sophisticated concurrent implementations, to reduce latency of individual request.

Design

• In-memory index -> concurrent data structure, and shared by all threads

• Compaction will be done on a dedicate thread

• KvsEngine and KvStore methods should take &self instead of &mut self, and impl Clone

• Trait ThreadPool

  ThreadPool::new(threads: u32) -> Result<ThreadPool>

  • Creates a new thread pool, immediately spawning the specified number of threads.
  • Returns an error if any thread fails to spawn. All previously-spawned threads are terminated.

  ThreadPool::spawn<F>(&self, job: F) where F: FnOnce() + Send + 'static

  • Spawn a function into the threadpool.
  • Spawning always succeeds, but if the function panics the threadpool continues to operate with the same number of threads — the thread count is not reduced nor is the thread pool destroyed, corrupted or invalidated.

Threadpool

3 Types thread pools

• NaiveThreadPool: this implementation is not going to reuse threads between jobs.
• SharedQueueThreadPool: Instead of creating a new thread for every multithreaded job to be performed, a thread pool maintains a "pool" of threads, and reuses those threads instead of creating a new one. If a thread in your pool panics, the thread dies and spawn another, panic will be catched and keep the existing thread running.
• RayonThreadPool: another threadpool implementation built by rayon::ThreadPool.