kopia lustrzana https://github.com/peterhinch/micropython-samples
87 wiersze
2.9 KiB
Python
87 wiersze
2.9 KiB
Python
# test_fast_scheduling.py Test fast_io PR
|
|
# https://github.com/micropython/micropython-lib/pull/287
|
|
|
|
# Test is designed to quantify the difference between fast and normal I/O without
|
|
# recourse to electronic testgear. Run on Pyboard.
|
|
|
|
# The MyIO class supports .readline() which updates a call counter and clears the
|
|
# .ready_rd flag. This is set by a timer (emulating the arrival of data from
|
|
# some hardware device).
|
|
# The .dummy method emulates a relatively slow user coro which yields with a zero
|
|
# delay; the test runs 10 instances of this. Each instance updates a common call
|
|
# counter.
|
|
# The receiver coro awaits .readline continuously. With normal scheduling each is
|
|
# scheduled after the ten .dummy instances have run. With fast scheduling and a
|
|
# timer period <= 10ms readline and dummy alternate. If timer period is increased
|
|
# readline is sheduled progressively less frequently.
|
|
|
|
import io
|
|
import pyb
|
|
import utime
|
|
import uasyncio as asyncio
|
|
import micropython
|
|
micropython.alloc_emergency_exception_buf(100)
|
|
|
|
MP_STREAM_POLL_RD = const(1)
|
|
MP_STREAM_POLL_WR = const(4)
|
|
MP_STREAM_POLL = const(3)
|
|
MP_STREAM_ERROR = const(-1)
|
|
|
|
class MyIO(io.IOBase):
|
|
def __init__(self):
|
|
self.read_count = 0
|
|
self.dummy_count = 0
|
|
self.ready_rd = False
|
|
pyb.Timer(4, freq = 100, callback = self.do_input)
|
|
|
|
# Read callback: emulate asynchronous input from hardware.
|
|
def do_input(self, t):
|
|
self.ready_rd = True # Data is ready to read
|
|
|
|
def ioctl(self, req, arg):
|
|
ret = MP_STREAM_ERROR
|
|
if req == MP_STREAM_POLL:
|
|
ret = 0
|
|
if arg & MP_STREAM_POLL_RD:
|
|
if self.ready_rd:
|
|
ret |= MP_STREAM_POLL_RD
|
|
return ret
|
|
|
|
def readline(self):
|
|
self.read_count += 1
|
|
self.ready_rd = False
|
|
return b'a\n'
|
|
|
|
async def dummy(self):
|
|
while True:
|
|
await asyncio.sleep(0)
|
|
self.dummy_count += 1
|
|
utime.sleep_ms(10) # Emulate time consuming user code
|
|
|
|
async def killer(self):
|
|
print('Test runs for 5s')
|
|
await asyncio.sleep(5)
|
|
print('I/O count {} Dummy count {}'.format(self.read_count, self.dummy_count))
|
|
|
|
async def receiver(myior, fast):
|
|
sreader = asyncio.StreamReader(myior)
|
|
if fast:
|
|
sreader.priority()
|
|
while True:
|
|
await sreader.readline()
|
|
|
|
def test(fast=False):
|
|
loop = asyncio.get_event_loop()
|
|
myior = MyIO()
|
|
loop.create_task(receiver(myior, fast))
|
|
for _ in range(10):
|
|
loop.create_task(myior.dummy())
|
|
loop.run_until_complete(myior.killer())
|
|
|
|
print('Test case of I/O competing with zero delay tasks.')
|
|
print('fast False, uasyncio V2: approx I/O count 25, dummy count 510.')
|
|
print('fast False, new uasyncio: I/O count 46, dummy 509.')
|
|
print('fast True, new uasyncio: approx I/O count 509, dummy count 509.')
|
|
print('Run test() to check I/O performance at normal priority.')
|
|
print('Run test(True) to check I/O performance at high priority.')
|