Memory Maps (MMAP) Deliver 25x Faster File Access in Go
6 months ago
- #system-calls
- #memory-maps
- #performance
- System calls are slow due to kernel entry costs.
- Memory maps allow files to be part of virtual memory, improving disk I/O performance.
- Memory maps reduce memory pressure and latency by using pointers.
- Writing to memory maps is inefficient due to page faults and OS overhead.
- Varnish Cache initially used memory maps for high performance but later switched to more efficient methods.
- Memory maps can significantly improve performance, as shown by a 25x improvement in a CDB implementation.
- Benchmarks and examples provided demonstrate the effectiveness and limitations of memory maps.