Understanding Go's garbage collector
7 days ago
- #memory-management
- #garbage-collection
- #golang
- Go's garbage collector (GC) is a concurrent, nongenerational, tri-color mark and sweep collector.
- The GC uses a pacer mechanism to determine when to trigger collection based on memory allocation rates and heap growth.
- The target heap memory is calculated using live heap size, GC roots, and the GOGC percentage (default 100%).
- GOMEMLIMIT is an option to set a memory limit, but misuse can lead to excessive GC cycles and CPU usage.
- The GC involves a mark phase with stop-the-world (STW) events for write barriers, followed by a lazy sweep phase.
- Tri-color marking categorizes objects as white (unreached), gray (in-progress), or black (processed and reachable).
- Go's GC is concurrent, meaning it runs alongside goroutines with minimal STW pauses for write barriers.
- Go's GC is nongenerational, meaning it does not differentiate objects by age, prioritizing simplicity and low latency.
- The Green Tea GC is an ongoing effort to improve Go's GC performance.
- Developers should be mindful of memory allocation to reduce GC overhead and improve application performance.