fix random Timer too close or Move queue overflow errors (#123)

shaketune/commands/accelerometer.py

@@ -9,15 +9,18 @@
 #              accelerometer measurements and write the data to a file in a blocking manner.
 
 
+import os
 import time
-
-# from ..helpers.console_output import ConsoleOutput
+from multiprocessing import Process, Queue
 
 
 class Accelerometer:
     def __init__(self, klipper_accelerometer):
         self._k_accelerometer = klipper_accelerometer
+
         self._bg_client = None
+        self._write_queue = Queue()
+        self._write_processes = []
 
     @staticmethod
     def find_axis_accelerometer(printer, axis: str = 'xy'):
@@ -32,7 +35,6 @@ class Accelerometer:
     def start_measurement(self):
         if self._bg_client is None:
             self._bg_client = self._k_accelerometer.start_internal_client()
-            # ConsoleOutput.print('Accelerometer measurements started')
         else:
             raise ValueError('measurements already started!')
 
@@ -54,12 +56,30 @@ class Accelerometer:
         bg_client.finish_measurements()
 
         filename = f'/tmp/shaketune-{name}.csv'
-        self._write_to_file(bg_client, filename)
-        # ConsoleOutput.print(f'Accelerometer measurements stopped. Data written to {filename}')
+        self._queue_file_write(bg_client, filename)
+
+    def _queue_file_write(self, bg_client, filename):
+        self._write_queue.put(filename)
+        write_proc = Process(target=self._write_to_file, args=(bg_client, filename))
+        write_proc.daemon = True
+        write_proc.start()
+        self._write_processes.append(write_proc)
 
     def _write_to_file(self, bg_client, filename):
+        try:
+            os.nice(20)
+        except Exception:
+            pass
         with open(filename, 'w') as f:
             f.write('#time,accel_x,accel_y,accel_z\n')
             samples = bg_client.samples or bg_client.get_samples()
             for t, accel_x, accel_y, accel_z in samples:
                 f.write(f'{t:.6f},{accel_x:.6f},{accel_y:.6f},{accel_z:.6f}\n')
+        self._write_queue.get()
+
+    def wait_for_file_writes(self):
+        while not self._write_queue.empty():
+            time.sleep(0.1)
+        for proc in self._write_processes:
+            proc.join()
+        self._write_processes = []