toolhead: Rework lookahead flush to be more stable during high cpu

Change the lookahead queue so that it attempts to buffer at least
buffer_time_high amount of moves when first starting a print.  This
helps ensure the buffer is normally always full.

If the buffer falls below buffer_time_low then it is either due to the
end of a print or because octoprint/klippy is unable to keep up.
Change the code so that in this case the lookahead queue will attempt
to gather buffer_time_high amount of moves before restarting movement.

Update the default buffer_time_low to 1 second and buffer_time_high to
2 seconds.  With the above changes a smaller buffer_time_high and a
larger buffer_time_low are more practical.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/scripts/graphstats.py b/scripts/graphstats.py
index 7600ee52..ef93e711 100755
--- a/scripts/graphstats.py
+++ b/scripts/graphstats.py
@@ -8,7 +8,7 @@ import optparse, datetime
 import matplotlib.pyplot as plt, matplotlib.dates as mdates
 
 MAXBANDWIDTH=25000.
-MAXBUFFER=5.
+MAXBUFFER=2.
 
 def parse_log(logname):
     f = open(logname, 'rb')
@@ -90,7 +90,7 @@ def plot_mcu(data, maxbw, outname):
     ax1.plot_date(times, bwdeltas, 'g', label='Bandwidth')
     ax1.plot_date(times, loads, 'r', label='MCU load')
     ax1.plot_date(times, hostbuffers, 'c', label='Host buffer')
-    ax1.legend()
+    ax1.legend(loc='best')
     ax1.xaxis.set_major_formatter(mdates.DateFormatter('%H:%M'))
     #plt.gcf().autofmt_xdate()
     ax1.grid(True)