Linux, Threads. Dining Philosophers (C language)
Overview
A multithreaded simulation of the classic Dining Philosophers Problem, implemented in C using POSIX threads.
Focuses on correct synchronization, deadlock avoidance, starvation prevention, and precise time management on Linux.
Source Code
Documentation
Purpose
- Understand concurrency and synchronization in Linux
- Practice thread-safe design with shared resources
- Prevent deadlocks and starvation in real scheduling conditions
- Build intuition for timing, scheduling, and race conditions
Technical Highlights
- One
pthreadper philosopher with shared fork resources - Mutex-based synchronization for forks and shared state
- Deadlock prevention via asymmetric fork acquisition strategy
- Starvation detection using a dedicated monitor thread
- Precise timing using
gettimeofday()and controlled sleep loops - Buffered logging system to reduce I/O contention
Architecture
- Central environment structure managing shared state
- Philosopher threads executing a finite-state routine
- Monitor thread supervising starvation and termination
- Logger thread batching and flushing output safely
- All mutexes and philosopher structures allocated contiguously
Performance Considerations
- Reduced system call overhead by avoiding frequent
usleep() - Buffered logging instead of frequent
printf()calls - Bitwise operations for low-cost state checks
- Deterministic fork pickup order to avoid circular waits
Correctness and Safety
- No deadlocks under tested configurations
- No starvation when meal limits are specified
- Thread safety verified with:
- ThreadSanitizer
- Valgrind
- Helgrind / DRD
Outcome
- Correct, stable multithreaded simulation under load
- Practical experience with race conditions and scheduling
- Strong foundation for concurrent programming and low-level debugging
- Direct relevance to systems programming and security-sensitive code