Jeremy Tregunna
02febadf5d
- Add WAL replicator component with entry capture, buffering, and subscriptions - Implement WAL entry serialization with checksumming - Add batch serialization for network-efficient transfers - Implement proper concurrency control with mutex protection - Add utility functions for entry size estimation - Create comprehensive test suite
46 lines
1.1 KiB
Go
46 lines
1.1 KiB
Go
package replication
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import (
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"sync"
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)
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// LamportClock implements a logical clock based on Lamport timestamps
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// for maintaining causal ordering of events in a distributed system.
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type LamportClock struct {
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counter uint64
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mu sync.Mutex
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}
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// NewLamportClock creates a new LamportClock instance
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func NewLamportClock() *LamportClock {
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return &LamportClock{counter: 0}
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}
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// Tick increments the clock and returns the new timestamp value
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func (c *LamportClock) Tick() uint64 {
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c.mu.Lock()
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defer c.mu.Unlock()
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c.counter++
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return c.counter
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}
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// Update updates the clock based on a received timestamp,
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// ensuring the local clock is at least as large as the received timestamp,
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// then increments and returns the new value
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func (c *LamportClock) Update(received uint64) uint64 {
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c.mu.Lock()
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defer c.mu.Unlock()
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if received > c.counter {
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c.counter = received
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}
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c.counter++
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return c.counter
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}
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// Current returns the current timestamp without incrementing the clock
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func (c *LamportClock) Current() uint64 {
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c.mu.Lock()
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defer c.mu.Unlock()
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return c.counter
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}
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