homework-jianmu/docs/examples/python/fast_write_example.py

226 lines
6.5 KiB
Python

# install dependencies:
# recommend python >= 3.8
#
import logging
import math
import multiprocessing
import sys
import time
import os
from multiprocessing import Process, Queue
from mockdatasource import MockDataSource
from queue import Empty
from typing import List
logging.basicConfig(stream=sys.stdout, level=logging.DEBUG, format="%(asctime)s [%(name)s] - %(message)s")
READ_TASK_COUNT = 1
WRITE_TASK_COUNT = 1
TABLE_COUNT = 1000
QUEUE_SIZE = 1000000
MAX_BATCH_SIZE = 3000
_DONE_MESSAGE = '__DONE__'
def get_connection():
"""
If variable TDENGINE_FIRST_EP is provided then it will be used. If not, firstEP in /etc/taos/taos.cfg will be used.
You can also override the default username and password by supply variable TDENGINE_USER and TDENGINE_PASSWORD
"""
import taos
firstEP = os.environ.get("TDENGINE_FIRST_EP")
if firstEP:
host, port = firstEP.split(":")
else:
host, port = None, 0
user = os.environ.get("TDENGINE_USER", "root")
password = os.environ.get("TDENGINE_PASSWORD", "taosdata")
return taos.connect(host=host, port=int(port), user=user, password=password)
# ANCHOR: read
def run_read_task(task_id: int, task_queues: List[Queue], infinity):
table_count_per_task = TABLE_COUNT // READ_TASK_COUNT
data_source = MockDataSource(f"tb{task_id}", table_count_per_task, infinity)
try:
for batch in data_source:
if isinstance(batch, tuple):
batch = [batch]
for table_id, rows in batch:
# hash data to different queue
i = table_id % len(task_queues)
# block putting forever when the queue is full
for row in rows:
task_queues[i].put(row)
if not infinity:
for queue in task_queues:
queue.put(_DONE_MESSAGE)
except KeyboardInterrupt:
pass
finally:
logging.info('read task over')
# ANCHOR_END: read
# ANCHOR: write
def run_write_task(task_id: int, queue: Queue, done_queue: Queue):
from sql_writer import SQLWriter
log = logging.getLogger(f"WriteTask-{task_id}")
writer = SQLWriter(get_connection)
lines = None
try:
while True:
over = False
lines = []
for _ in range(MAX_BATCH_SIZE):
try:
line = queue.get_nowait()
if line == _DONE_MESSAGE:
over = True
break
if line:
lines.append(line)
except Empty:
time.sleep(0.1)
if len(lines) > 0:
writer.process_lines(lines)
if over:
done_queue.put(_DONE_MESSAGE)
break
except KeyboardInterrupt:
pass
except BaseException as e:
log.debug(f"lines={lines}")
raise e
finally:
writer.close()
log.debug('write task over')
# ANCHOR_END: write
def set_global_config():
argc = len(sys.argv)
if argc > 1:
global READ_TASK_COUNT
READ_TASK_COUNT = int(sys.argv[1])
if argc > 2:
global WRITE_TASK_COUNT
WRITE_TASK_COUNT = int(sys.argv[2])
if argc > 3:
global TABLE_COUNT
TABLE_COUNT = int(sys.argv[3])
if argc > 4:
global QUEUE_SIZE
QUEUE_SIZE = int(sys.argv[4])
if argc > 5:
global MAX_BATCH_SIZE
MAX_BATCH_SIZE = int(sys.argv[5])
# ANCHOR: monitor
def run_monitor_process(done_queue: Queue):
log = logging.getLogger("DataBaseMonitor")
conn = None
try:
conn = get_connection()
def get_count():
res = conn.query("SELECT count(*) FROM test.meters")
rows = res.fetch_all()
return rows[0][0] if rows else 0
last_count = 0
while True:
try:
done = done_queue.get_nowait()
if done == _DONE_MESSAGE:
break
except Empty:
pass
time.sleep(10)
count = get_count()
log.info(f"count={count} speed={(count - last_count) / 10}")
last_count = count
finally:
conn.close()
# ANCHOR_END: monitor
# ANCHOR: main
def main(infinity):
set_global_config()
logging.info(f"READ_TASK_COUNT={READ_TASK_COUNT}, WRITE_TASK_COUNT={WRITE_TASK_COUNT}, "
f"TABLE_COUNT={TABLE_COUNT}, QUEUE_SIZE={QUEUE_SIZE}, MAX_BATCH_SIZE={MAX_BATCH_SIZE}")
conn = get_connection()
conn.execute("DROP DATABASE IF EXISTS test")
conn.execute("CREATE DATABASE IF NOT EXISTS test keep 36500")
conn.execute("CREATE STABLE IF NOT EXISTS test.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) "
"TAGS (location BINARY(64), groupId INT)")
conn.close()
done_queue = Queue()
monitor_process = Process(target=run_monitor_process, args=(done_queue,))
monitor_process.start()
logging.debug(f"monitor task started with pid {monitor_process.pid}")
task_queues: List[Queue] = []
write_processes = []
read_processes = []
# create task queues
for i in range(WRITE_TASK_COUNT):
queue = Queue()
task_queues.append(queue)
# create write processes
for i in range(WRITE_TASK_COUNT):
p = Process(target=run_write_task, args=(i, task_queues[i], done_queue))
p.start()
logging.debug(f"WriteTask-{i} started with pid {p.pid}")
write_processes.append(p)
# create read processes
for i in range(READ_TASK_COUNT):
queues = assign_queues(i, task_queues)
p = Process(target=run_read_task, args=(i, queues, infinity))
p.start()
logging.debug(f"ReadTask-{i} started with pid {p.pid}")
read_processes.append(p)
try:
monitor_process.join()
for p in read_processes:
p.join()
for p in write_processes:
p.join()
time.sleep(1)
return
except KeyboardInterrupt:
monitor_process.terminate()
[p.terminate() for p in read_processes]
[p.terminate() for p in write_processes]
[q.close() for q in task_queues]
def assign_queues(read_task_id, task_queues):
"""
Compute target queues for a specific read task.
"""
ratio = WRITE_TASK_COUNT / READ_TASK_COUNT
from_index = math.floor(read_task_id * ratio)
end_index = math.ceil((read_task_id + 1) * ratio)
return task_queues[from_index:end_index]
if __name__ == '__main__':
multiprocessing.set_start_method('spawn')
main(False)
# ANCHOR_END: main