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Introductions

SeasSnowflake is a distributed unique ID generator inspired by Twitter's Snowflake.

Parts of a snowflake ID:

sign bit: will always be 0

this is because some languages don't support unsigned integers properly (Java and PHP are notable cases)

next 41 bits: milliseconds since custom epoch

next 10 bits: sequence id

lowest 12 bits: sequence number

How it Works

Each time you generate an ID, it works, like this.

A timestamp with millisecond precision is stored using 41 bits of the ID.

Then the work id and datacenter id is added in subsequent bits.

Then the Sequence Number is added, starting at 0 and incrementing for each ID generated in the same millisecond.

If you generate enough IDs in the same millisecond that the sequence would roll over or overfill then the generate function will pause until the next millisecond.

Benchmark test：

--TEST--
SeasSnowflake testBenchmark
--FILE--
<?php
//test code
$config=['worker_id'=>10,'datacenter_id'=>1];
$client = new SeasSnowflake($config);
$start = microtime(true);
for($i=0;$i<100000;$i++){
    $id= $client->generate();
}
$end = (float)microtime(true);
echo 'cost:'.round($end-$start,6).' second ';

echo ' and memory usage: ' . memory_get_usage() . 'byte';

?>

---- ACTUAL OUTPUT
cost:0.731212 second  and memory usage: 387520byte
---- FAILED

---- ACTUAL OUTPUT
make 100000 id=================
cost:0.712473 second  and memory usage: 395816byte
make 200000 id=================
cost:1.401492 second  and memory usage: 395816byte
make 300000 id=================
cost:1.415514 second  and memory usage: 395816byte
make 500000 id=================
cost:1.422977 second  and memory usage: 395816byte
---- FAILED

3、Benchmark code：More examples

How to use it：

Building

phpize
./configure
make
sudo make install

Once built and installed, be sure to add 'seassnowflake.so' to the php.ini extensions configuration.

extension=SeasSnowflake.so

$config=["worker_id"=>1,"datacenter_id"=>2];
$client = new SeasSnowflake($config);
$id= $client->generate();
var_dump("id is ====",$id);
$data=$client->degenerate($id);
var_dump("data is ====",$data);

echo:

string(10) "id is ===="
int(273387429541355520)
string(12) "data is ===="
array(6) {
  ["worker_id"]=>
  int(10)
  ["datacenter_id"]=>
  int(15)
  ["sequence"]=>
  int(0)
  ["timestamp"]=>
  int(1626140642495)
  ["begin_timestamp"]=>
  int(1560960000000)
  ["interval"]=>
  int(65180642495)
}

More examples

Support

SeasX Group