NXID: Generate XID by nanosecond

Package nxid is a nanosecond-level globally unique ID generator library, derived from XID. NXID is specifically designed for scenarios requiring high-resolution timestamp precision.

Key Changes from Original XID

• Utilizes an 8-byte nanosecond-level timestamp instead of a 4-byte second-level timestamp.
• Better suited for time-sensitive ID generation, ensuring higher resolution timing.

Structure

• 8-byte value representing the nanoseconds since the Unix epoch,
• 3-byte machine identifier,
• 2-byte process ID, and
• 3-byte counter, starting with a random value.

The binary representation of the ID remains compatible with MongoDB's 12-byte Object IDs, but the time precision is significantly higher.

Advantages

• Higher time resolution, making it suitable for applications where timestamp precision is essential.
• Compact and URL-safe string representation (20 chars).

Comparison

Name	Binary Size	String Size	Features
UUID	16 bytes	36 chars	configuration-free, not sortable
shortuuid	16 bytes	22 chars	configuration-free, not sortable
Snowflake	8 bytes	up to 20 chars	requires machine/DC configuration, central server, sortable
MongoID	12 bytes	24 chars	configuration-free, sortable
xid	12 bytes	20 chars	configuration-free, sortable, second-level precision
nxid	16 bytes	26 chars	configuration-free, sortable, nanosecond-level precision

Features

• Base32 hex encoded (20 chars when transported as a printable string, still sortable)
• Configuration-free, no need for unique machine or data center IDs
• K-ordered
• Embedded time with nanosecond precision
• Uniqueness guaranteed for 16,777,216 (24 bits) unique IDs per nanosecond and per host/process
• Lock-free generation

Installation

go get github.com/ClayCheung/nxid

Usage

Generate a new NXID:

guid := nxid.New()

println(guid.String())
// Output example: 2vmide3burdh0kb22i1m0pln98

Retrieve embedded info:

guid.Machine()
guid.Pid()
guid.Time()
guid.Counter()

Benchmark

run benchmark in id_benchmark_test.go

# go test -bench=. -benchmem -cpu=1,2,4
BenchmarkNXID           22169484                52.01 ns/op            0 B/op          0 allocs/op
BenchmarkNXID-2         26748993                43.79 ns/op            0 B/op          0 allocs/op
BenchmarkNXID-4         31624129                42.95 ns/op            0 B/op          0 allocs/op
BenchmarkXID            24247342                49.69 ns/op            0 B/op          0 allocs/op
BenchmarkXID-2          27107719                42.16 ns/op            0 B/op          0 allocs/op
BenchmarkXID-4          35370450                46.31 ns/op            0 B/op          0 allocs/op
BenchmarkGoUUIDv1       12962964                92.62 ns/op           48 B/op          1 allocs/op
BenchmarkGoUUIDv1-2     10513396               113.9 ns/op            48 B/op          1 allocs/op
BenchmarkGoUUIDv1-4      7847894               152.9 ns/op            48 B/op          1 allocs/op
BenchmarkUUIDv4         11317635               106.7 ns/op            64 B/op          2 allocs/op
BenchmarkUUIDv4-2        9622802               124.1 ns/op            64 B/op          2 allocs/op
BenchmarkUUIDv4-4        8338959               143.7 ns/op            64 B/op          2 allocs/op
BenchmarkUUIDv6         12215884                96.62 ns/op           48 B/op          1 allocs/op
BenchmarkUUIDv6-2        9493748               125.4 ns/op            48 B/op          1 allocs/op
BenchmarkUUIDv6-4        7318026               167.4 ns/op            48 B/op          1 allocs/op
BenchmarkUUIDv7          7409154               161.3 ns/op            64 B/op          2 allocs/op
BenchmarkUUIDv7-2        6529828               183.6 ns/op            64 B/op          2 allocs/op
BenchmarkUUIDv7-4        6162991               194.6 ns/op            64 B/op          2 allocs/op

Licensing

All source code is licensed under the MIT License.

---

References

• Original XID: https://github.com/rs/xid