Distributed unique ID generation service

Options:

• Random
  • Universally unique identifier (UUID)
• DB Auto-increment
  • Ticket server
  • Multi-ticket server
• Physical clock
  • Unix Timestamp
  • Twitter snowflake ID (Timestamp + workerID + sequenceNumber)
• Logical clock
  • Lamport clocks
  • Vector clocks
• TrueTime API

UUID

128-bit (16B) number. conflict概率极低:

After generating 1 billion UUIDs every second for approximately 100 years would the probability of creating a single duplicate reach 50%

Example: 09c93e62-50b4-468d-bf8a-c07e1040bfb2

Pros:

• Simple. Generating UUID is simple. No coordination between servers is needed so there will not be any synchronization issues.
• Scalable. The system is easy to scale because each web server is responsible for generating IDs they consume. ID generator can easily scale with web servers.
• Available.

Cons:

• IDs are 128 bits long, but our requirement is 64 bits.
• IDs could be non-numeric.