go-lock

go-lock is a lock library implementing read-write mutex and read-write trylock without starvation

Description

go-lock is a Golang library implementing an efficient read-write lock with the following built-in mechanism: - Mutex - Trylock - No-starve read-write solution

Native sync/Mutex and sync/RWMutex are very powerful and reliable. However, it became a disaster if the lock was not released as expected. Or someone was holding the lock too long at the peak time. It slowed down whole system. Dealing with those cases, go-lock implements TryLock, TryLockWithTimeout and TryLockWithContext function in addition to Lock and Unlock. It provides flexibility to control the resources.

Programming language: Go

License: Apache License 2.0

Tags: Go Tools     Go     Golang     Mutex     Trylock     Spinlock     Readwritelock    

Latest version: v1.0.1

README

go-lock

go-lock is a Golang library implementing an effcient read-write lock with the following built-in mechanism:

• Mutex with timeout mechanism
• Trylock
• No-starve read-write solution

Native sync/Mutex and sync/RWMutex are very powerful and reliable. However, it became a disaster if the lock was not released as expected. Or, someone was holding the lock too long at the peak time leading whole system blocked. Dealing with those cases, go-lock implements TryLock, TryLockWithTimeout and TryLockWithContext function in addition to Lock and Unlock. It provides flexibility to control the resources.

Installation

go get github.com/viney-shih/go-lock

Example

package main

import (
    "fmt"
    "sync/atomic"
    "time"

    lock "github.com/viney-shih/go-lock"
)

func main() {
    // set RWMutex with CAS mechanism (CASMutex).
    var rwMut lock.RWMutex = lock.NewCASMutex()
    // set default value
    count := int32(0)

    // block here
    rwMut.Lock()
    go func() {
        time.Sleep(50 * time.Millisecond)
        fmt.Println("Now is", atomic.AddInt32(&count, 1)) // Now is 1
        rwMut.Unlock()
    }()

    // waiting for previous goroutine releasing the lock, and locking it again
    rwMut.Lock()
    fmt.Println("Now is", atomic.AddInt32(&count, 2)) // Now is 3

    // TryLock without blocking
    // Return false, because the lock is not released.
    fmt.Println("Return", rwMut.TryLock())

    // RTryLockWithTimeout without blocking
    // Return false, because the lock is not released.
    fmt.Println("Return", rwMut.RTryLockWithTimeout(50*time.Millisecond))

    // TryLockWithContext without blocking
    ctx, cancel := context.WithTimeout(context.TODO(), 50*time.Millisecond)
    defer cancel()
    // Return false, because the lock is not released.
    fmt.Println("Return", rwMut.TryLockWithContext(ctx))

    // release the lock in the end.
    rwMut.Unlock()

    // Output:
    // Now is 1
    // Now is 3
    // Return false
    // Return false
    // Return false
}

• [More examples](./cas_test.go)
• Full API documentation

Benchmarks

• Run on MacBook Pro (Retina, 15-inch, Mid 2015) 2.5 GHz Quad-Core Intel Core i7 16 GB 1600 MHz DDR3 using Go 1.15.2
• Run with 1, 2, 4, 8 and 16 cpu to show it scales well...16 is double the # of logical cores on this machine.

go test -cpu=1,2,4,8,16 -bench=. -benchmem=true

goos: darwin
goarch: amd64
pkg: github.com/viney-shih/go-lock

(sync.RWMutex)
BenchmarkRWMutexLock                        42591765            27.4 ns/op         0 B/op          0 allocs/op
BenchmarkRWMutexLock-2                      42713179            27.5 ns/op         0 B/op          0 allocs/op
BenchmarkRWMutexLock-4                      44348323            27.5 ns/op         0 B/op          0 allocs/op
BenchmarkRWMutexLock-8                      44135148            27.9 ns/op         0 B/op          0 allocs/op
BenchmarkRWMutexLock-16                     43566165            27.5 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentRWMutexLock              42971319            27.5 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentRWMutexLock-2            20131005            57.5 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentRWMutexLock-4            10752337           115 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrentRWMutexLock-8            11434335           105 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrentRWMutexLock-16           10495626           109 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrent50RWMutexLock            27979630            42.8 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrent50RWMutexLock-2          13037742            86.6 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrent50RWMutexLock-4           9143397           134 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrent50RWMutexLock-8           8335652           139 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrent50RWMutexLock-16          7876855           150 ns/op           0 B/op          0 allocs/op

(ChanMutex)
BenchmarkChanMutexLock                      22619928            51.8 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexLock-2                    22769630            51.6 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexLock-4                    23096103            51.7 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexLock-8                    22627267            51.1 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexLock-16                   23092266            51.7 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexLock            23422556            51.8 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexLock-2           6101949           201 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexLock-4           5882083           200 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexLock-8           5827183           211 ns/op           0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexLock-16          5577098           215 ns/op           0 B/op          0 allocs/op
BenchmarkChanMutexTryLock                   22272500            51.8 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexTryLock-2                 23004806            52.2 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexTryLock-4                 22461870            52.3 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexTryLock-8                 22901328            53.8 ns/op         0 B/op          0 allocs/op
BenchmarkChanMutexTryLock-16                22334739            55.4 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexTryLock         22112250            53.9 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexTryLock-2       13806072            85.0 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexTryLock-4       45892635            32.6 ns/op         0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexTryLock-8       396310569            2.86 ns/op        0 B/op          0 allocs/op
BenchmarkConcurrentChanMutexTryLock-16      512990590            2.35 ns/op        0 B/op          0 allocs/op

(CASMutex)
BenchmarkCASMutexLock                        6160122           186 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexLock-2                      7507022           156 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexLock-4                      7646648           156 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexLock-8                      7559616           156 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexLock-16                     7576237           158 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrentCASMutexLock              6375879           185 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrentCASMutexLock-2            1690890           706 ns/op         251 B/op          3 allocs/op
BenchmarkConcurrentCASMutexLock-4            1677104           714 ns/op         255 B/op          3 allocs/op
BenchmarkConcurrentCASMutexLock-8            1808582           639 ns/op         255 B/op          3 allocs/op
BenchmarkConcurrentCASMutexLock-16           1918422           622 ns/op         255 B/op          3 allocs/op
BenchmarkConcurrent50CASMutexLock            5650274           210 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrent50CASMutexLock-2          1698381           707 ns/op         247 B/op          3 allocs/op
BenchmarkConcurrent50CASMutexLock-4          1697070           707 ns/op         255 B/op          3 allocs/op
BenchmarkConcurrent50CASMutexLock-8          1809859           655 ns/op         255 B/op          3 allocs/op
BenchmarkConcurrent50CASMutexLock-16         1801652           646 ns/op         256 B/op          4 allocs/op
BenchmarkCASMutexTryLock                     6593228           182 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexTryLock-2                   7703084           154 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexTryLock-4                   7790750           151 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexTryLock-8                   7756263           152 ns/op          96 B/op          1 allocs/op
BenchmarkCASMutexTryLock-16                  7741186           152 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrentCASMutexTryLock           6509828           189 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrentCASMutexTryLock-2        14058355            82.2 ns/op        17 B/op          0 allocs/op
BenchmarkConcurrentCASMutexTryLock-4        16875369            71.4 ns/op         8 B/op          0 allocs/op
BenchmarkConcurrentCASMutexTryLock-8        10985379           109 ns/op           4 B/op          0 allocs/op
BenchmarkConcurrentCASMutexTryLock-16       12405752           104 ns/op           1 B/op          0 allocs/op
BenchmarkConcurrent50CASMutexTryLock         5631146           204 ns/op          96 B/op          1 allocs/op
BenchmarkConcurrent50CASMutexTryLock-2       6518946           182 ns/op          61 B/op          0 allocs/op
BenchmarkConcurrent50CASMutexTryLock-4       6937346           174 ns/op          43 B/op          0 allocs/op
BenchmarkConcurrent50CASMutexTryLock-8       6493034           182 ns/op          39 B/op          0 allocs/op
BenchmarkConcurrent50CASMutexTryLock-16      6177854           202 ns/op          41 B/op          0 allocs/op
PASS

References

• https://github.com/golang/go/issues/6123
• https://github.com/LK4D4/trylock
• https://github.com/OneOfOne/go-utils/tree/master/sync
• https://github.com/lrita/gosync
• https://github.com/google/netstack/blob/master/tmutex/tmutex.go
• https://github.com/subchen/go-trylock

License

Apache-2.0