Anti-patterns related to shared resource access that can lead to performance bottlenecks and application instability.
Resource Contention Overview
Resource contention occurs when multiple threads, processes, or systems compete for access to shared resources such as CPU, memory, database connections, or file handles. This contention can lead to performance degradation, deadlocks, and application instability.
Common resource contention issues include:
This guide covers common anti-patterns related to resource contention and provides best practices for optimizing resource usage across different application types.
Excessive Locking
Excessive locking, particularly using coarse-grained locks for all operations, leads to unnecessary contention, reduced concurrency, and poor application performance.
To optimize locking strategies:
Connection Pool Exhaustion
Connection pool exhaustion occurs when an application fails to properly release database connections back to the pool, leading to resource starvation and eventual application failure.
To prevent connection pool exhaustion:
Thread Pool Saturation
Thread pool saturation occurs when an application submits more tasks than the thread pool can handle, leading to task queuing, increased latency, and potential resource exhaustion.
To prevent thread pool saturation:
Database Lock Contention
Database lock contention occurs when multiple transactions compete for the same database locks, leading to reduced concurrency, increased latency, and potential deadlocks.
To minimize database lock contention:
Resource Leaks
Resource leaks occur when an application fails to properly release resources such as file handles, database connections, or network sockets, leading to resource exhaustion and eventual application failure.
To prevent resource leaks:
Memory Contention
Memory contention occurs when multiple processes or threads compete for limited memory resources, leading to increased garbage collection, swapping, and potential out-of-memory errors.
To minimize memory contention:
CPU Contention
CPU contention occurs when multiple processes or threads compete for limited CPU resources, leading to increased latency, reduced throughput, and poor application responsiveness.
To minimize CPU contention:
Deadlocks
Deadlocks occur when two or more threads are blocked forever, waiting for each other to release locks, leading to application hangs and unresponsiveness.
To prevent deadlocks:
I/O Contention
I/O contention occurs when multiple processes or threads compete for limited I/O resources such as disk or network bandwidth, leading to increased latency and reduced throughput.
To minimize I/O contention:
Resource Contention Checklist
Preventing resource contention requires a systematic approach that addresses multiple aspects of resource usage, from locking strategies to thread pool management and I/O operations.
Key prevention strategies: