From 326413a2715e58432a96d63e3eb1025fa2226348 Mon Sep 17 00:00:00 2001
From: Quentin Pradet <quentin.pradet@gmail.com>
Date: Fri, 16 Nov 2018 16:48:36 +0400
Subject: [PATCH 1/2] Use time.monotonic if available

---
 progress/__init__.py | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/progress/__init__.py b/progress/__init__.py
index 122406f..ebd7908 100644
--- a/progress/__init__.py
+++ b/progress/__init__.py
@@ -18,7 +18,10 @@ from collections import deque
 from datetime import timedelta
 from math import ceil
 from sys import stderr
-from time import time
+try:
+    from time import monotonic
+except ImportError:
+    from time import time as monotonic
 
 
 __version__ = '1.4'
@@ -35,7 +38,7 @@ class Infinite(object):
 
     def __init__(self, message='', **kwargs):
         self.index = 0
-        self.start_ts = time()
+        self.start_ts = monotonic()
         self.avg = 0
         self._ts = self.start_ts
         self._xput = deque(maxlen=self.sma_window)
@@ -58,7 +61,7 @@ class Infinite(object):
 
     @property
     def elapsed(self):
-        return int(time() - self.start_ts)
+        return int(monotonic() - self.start_ts)
 
     @property
     def elapsed_td(self):
@@ -102,7 +105,7 @@ class Infinite(object):
         return self.file.isatty() if self.check_tty else True
 
     def next(self, n=1):
-        now = time()
+        now = monotonic()
         dt = now - self._ts
         self.update_avg(n, dt)
         self._ts = now

From c1e07104e1debb90be7c58168d601c3e820b77b7 Mon Sep 17 00:00:00 2001
From: Quentin Pradet <quentin.pradet@gmail.com>
Date: Fri, 16 Nov 2018 16:52:10 +0400
Subject: [PATCH 2/2] Update avg/eta/eta_td less frequently

When the progress bar is updated frequently (every few milliseconds),
the eta can change so quickly that it's impossible to read.

This commit updates the average while sma_window is being filled, then
after every second.

This means we're calling monotonic/time often, but those calls take less
than 100 nsec per loop on Linux, Windows and macOS [0], which is
equivalent to one attribute lookup or two.

[0]: https://github.com/python-trio/trio/issues/33
---
 progress/__init__.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/progress/__init__.py b/progress/__init__.py
index ebd7908..ca7f6b4 100644
--- a/progress/__init__.py
+++ b/progress/__init__.py
@@ -40,6 +40,7 @@ class Infinite(object):
         self.index = 0
         self.start_ts = monotonic()
         self.avg = 0
+        self._avg_update_ts = self.start_ts
         self._ts = self.start_ts
         self._xput = deque(maxlen=self.sma_window)
         for key, val in kwargs.items():
@@ -69,8 +70,14 @@ class Infinite(object):
 
     def update_avg(self, n, dt):
         if n > 0:
+            xput_len = len(self._xput)
             self._xput.append(dt / n)
-            self.avg = sum(self._xput) / len(self._xput)
+            now = monotonic()
+            # update when we're still filling _xput, then after every second
+            if (xput_len < self.sma_window or
+                    now - self._avg_update_ts > 1):
+                self.avg = sum(self._xput) / len(self._xput)
+                self._avg_update_ts = now
 
     def update(self):
         pass