Package mutex provides multiple mutual exclusion lock. The name is constructed by combining a common name for mutual exclusion locks, Mutex, and word multiple, which is a property of this specific implementation. Multex locking and unlocking for a single key is a few times slower then locking with sync.Mutex, but provides the ability to lock the same block of code with specific keys, allowing concurrent execution of the same code only for different keys.
Performance comparison of Multex with a single key and sync.Mutex can be done by running benchmarks in this package.
BenchmarkMultex-10 39488458 26.89 ns/op 0 B/op 0 allocs/op
BenchmarkMutex-10 86903780 13.41 ns/op 0 B/op 0 allocs/op
Run go get resenje.org/multex from command line.