import logging
import time
class
generator
(object):
""" 64位id 1(符號位不用) (41(毫秒)+4(機器id)+6(業務編碼)+12(重複累加))
基礎時間(毫秒): 1577808000000 2020/01/01/ 00:00
最大支援時間差: 2199023255551(0x1ffffffffffbit) 基於毫秒算大約可用69年(2199023255551/1000/60/60/24/365.25)
dc: 4bit (自動取值範圍[0,16))
worker: 6bit (自動取值範圍[0,64))
desc: 同一時刻產生4095個id,原理上支援每秒409.5萬個id，由於執行效率問題，本程式經測試每秒約能產生70萬個id
"""epoch_timestamp =
1577808000000
max_sequence =
4095
# 12bit 最大值
def__init__
(self, dc, worker)
: self.dc = dc
self.worker = worker
self.node_id =
((dc &
0xf)
<<6)
|(worker &
0x3f
)# 10bit = 4bit + 6bit
self.last_timestamp = self.epoch_timestamp
self.sequence =
0 self.sequence_overload =
0 self.errors =
0 self.generated_ids =
0def
get_next_id
(self)
:""" id生產
"""curr_time =
int(time.time()*
1000
)if curr_time < self.last_timestamp:
# stop handling requests til we've caught back up
self.errors +=
1raise exception(
'clock went backwards! %d < %d'
%(curr_time, self.last_timestamp)
)if curr_time > self.last_timestamp:
self.sequence =
0 self.last_timestamp = curr_time
self.sequence +=
1if self.sequence > self.max_sequence:
# the sequence is overload, just wait to next sequence
logging.warning(
'the sequence has been overload'
) self.sequence_overload +=
1 time.sleep(
0.001
)return self.get_next_id(
) diff_time = curr_time - self.epoch_timestamp
generated_id =
((diff_time &
0x1ffffffffff
)<<22)
|(self.node_id <<12)
| self.sequence
self.generated_ids +=
1return generated_id
@property
defstats
(self)
:""" 狀態查詢
"""return
defpressure_test
(self)
:""" 壓力測試
"""start_time =
int(time.time()*
1000
) end_time =
1000
+ start_time
id_num =
0while self.last_timestamp <= end_time:
self.get_next_id(
) id_num +=
1print
(id_num)
if __name__ ==
'__main__'
: a = generator(0,
0)a.pressure_test(
)
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