Updating map import time estimates.

Author: lrnselfreliance

modules/map/lib.py

@@ -222,34 +222,27 @@ def get_import_status(session: Session = None) -> List[MapFile]:
 
 
 # Calculated using many tests on a well-cooled RPi4 (4GB).
-RPI4_PBF_BYTES_PER_SECOND = 61879
-RPI4_A = 7.17509261732342e-14
-RPI4_B = 6.6590760410412e-5
-RPI4_C = 10283
+RPI4_PBF_BYTES_PER_SECOND = 175473
+RPI4_COEFFICIENTS = [4.01229956e-15, 7.19038150e-06, -1.36868043e+02]
 # Calculated using many tests on a well-cooled RPi5 (8GB).
 RPI5_PBF_BYTES_PER_SECOND = 136003
-RPI5_A = 1.6681382703586e-15
-RPI5_B = 2.35907824676145e-6
-RPI5_C = 53.727
+RPI_5COEFFICIENTS = [1.66813827e-15, 2.35907825e-06, 5.37276181e+01]
 
 
 def seconds_to_import_rpi4(size_in_bytes: int) -> int:
     if size_in_bytes > 1_000_000_000:
         # Use exponential curve for large files.
-        a = RPI4_A * size_in_bytes ** 2
-        b = RPI4_B * size_in_bytes
-        return int(a - b + RPI4_C)
+        a, b, c = RPI4_COEFFICIENTS
+        return int(a * size_in_bytes ** 2 + b * size_in_bytes + c)
     # Use simpler equation for small files.
     return max(int(size_in_bytes // RPI4_PBF_BYTES_PER_SECOND), 0)
 
 
 def seconds_to_import_rpi5(size_in_bytes: int) -> int:
-    if size_in_bytes > 5_000_000_000:
+    if size_in_bytes > 1_000_000_000:
         # Use exponential curve for large files.
-        a = RPI5_A * size_in_bytes ** 2
-        b = RPI5_B * size_in_bytes
-        return int(a - b + RPI5_C)
-    # Use simpler equation for small files.
+        a, b, c = RPI_5COEFFICIENTS
+        return int(a * size_in_bytes ** 2 + b * size_in_bytes + c)
     return max(int(size_in_bytes // RPI5_PBF_BYTES_PER_SECOND), 0)
 
 

modules/map/test/test_lib.py

@@ -69,15 +69,15 @@ async def test_run_import_command(test_directory, mock_run_command, run_command_
 @pytest.mark.parametrize('size,expected', [
     (0, 0),
     (-1, 0),
-    (17737381, 286),
-    (63434267, 1025),
-    (87745484, 1418),
-    (116318111, 1879),
-    (136372996, 2203),
-    (1936075318, 150308),
-    (2676094489, 345922),
-    (3392375001, 610106),
-    (11346305075, 8491840),
+    (17737381, 101),
+    (63434267, 361),
+    (87745484, 500),
+    (116318111, 662),
+    (136372996, 777),
+    (1936075318, 28823),
+    (2676094489, 47839),
+    (3392375001, 70429),
+    (11346305075, 597985),
 ])
 def test_seconds_to_import_rpi4(size, expected):
     assert lib.seconds_to_import(size) == expected
@@ -91,10 +91,10 @@ def test_seconds_to_import_rpi4(size, expected):
     (87745484, 645),
     (116318111, 855),
     (136372996, 1002),
-    (1936075318, 14235),
-    (2676094489, 19676),
-    (3392375001, 24943),
-    (11346305075, 188040),
+    (1936075318, 10873),
+    (2676094489, 18313),
+    (3392375001, 27253),
+    (11346305075, 241574),
 ])
 def test_seconds_to_import_rpi5(size, expected):
     assert lib.seconds_to_import(size, True) == expected