Switch to Matplotlib from Gnuplot

scripts/wk/graph.py

@@ -4,23 +4,22 @@
 import base64
 import json
 import logging
-import math
 import pathlib
 import time
 
+from matplotlib import pyplot
 import requests
-import Gnuplot
 
 from wk.cfg.net import BENCHMARK_SERVER, IMGUR_CLIENT_ID
 from wk.ui import ansi
 
 
-# Hack to hide X11 error when running in CLI mode
-Gnuplot.gp.GnuplotOpts.default_term = 'xterm'
-
-
 # STATIC VARIABLES
 LOG = logging.getLogger(__name__)
+GRAPH_FIGURE_SIZE = (
+  9.167, # 660px at 72dpi
+  4.167, # 300px at 72dpi
+)
 GRAPH_HORIZONTAL = ('▁', '▂', '▃', '▄', '▅', '▆', '▇', '█')
 GRAPH_VERTICAL = (
     '▏',    '▎',    '▍',    '▌',
@@ -57,32 +56,23 @@ def export_io_graph(disk, log_dir, read_rates):
   max_rate = max(read_rates) / (1024**2)
   max_rate = max(800, max_rate)
   out_path = pathlib.Path(f'{log_dir}/{disk.path.name}_iobenchmark.png')
-  plot_data = out_path.with_suffix('.data')
+  plot_data = ([], [])
 
-  # Adjust Y-axis range to either 1000 or roughly max rate + 200
-  ## Round up to the nearest 100 and then add 200
-  y_range = (math.ceil(max_rate/100)*100) + 200
+  # Prep data for graph
+  for i, rate in enumerate(read_rates):
+    plot_data[0].append((i+1) / len(read_rates) * 100)  # Step
+    plot_data[1].append(int(rate / (1024**2)))          # Data
 
-  # Save plot data to file for Gnuplot
-  with open(plot_data, 'w', encoding='utf-8') as _f:
-    for i, rate in enumerate(read_rates):
-      percent = (i+1) / len(read_rates) * 100
-      rate = int(rate / (1024**2))
-      _f.write(f'{percent:0.1f} {rate}\n')
-
-  # Run gnuplot commands
-  _g = Gnuplot.Gnuplot()
-  _g('reset')
-  _g(f'set output "{out_path}"')
-  _g('set terminal png large size 660,300 truecolor font "Noto Sans,11"')
-  _g('set title "I/O Benchmark"')
-  _g(f'set yrange [0:{y_range}]')
-  _g('set style data lines')
-  _g(f'plot "{plot_data}" title "{disk.description.replace("_", " ")}"')
-
-  # Cleanup
-  _g.close()
-  del _g
+  # Build graph
+  _, ax = pyplot.subplots(
+    dpi=72,
+    figsize=GRAPH_FIGURE_SIZE,
+    layout='constrained',
+    )
+  ax.set_title('I/O Benchmark')
+  ax.plot(*plot_data, label=disk.description.replace('_', ' '))
+  ax.legend()
+  pyplot.savefig(out_path)
 
   return out_path
 

scripts/wk/hw/benchmark.py

@@ -153,8 +153,9 @@ def export_and_upload_graphs(state, test_obj, rate_list):
   image_path = None
   try:
     image_path = graph.export_io_graph(test_obj.dev, state.log_dir, rate_list)
-  except RuntimeError:
+  except RuntimeError as err:
     # Failed to export PNG, skip uploads below
+    LOG.error('Failed to export graph: %s', err)
     test_obj.report.append('Failed to export graph')
     return