latency-graph.py: Generates graph for the delete latencies in PG

This script fetches the top N latency durations from the log file and generates a graph for the same.
Latencies vs Time

Signed-off-by: Pawan Dhiran <[email protected]>

Author: pdhiran

rados/long-running/1.sh

@@ -0,0 +1,88 @@
+"""
+Module used to:
+1. Collect the latencies from the provided logs,
+2. generates a graph for the top N latencies against time
+
+The input file is a modified file, which contains  latencies are grepped from ceph OSD log for faster run.
+-> grep -a dequeue_op.*latency ceph-osd.log > latencies.log
+( Performed to reduce run time, since lots of logging would be generated )
+
+NOTE : The debug levels for the OSD for the latencies to be captured,
+        the Param: debug_osd needs to be set to 20 globally
+"""
+
+import re
+import sys
+from datetime import datetime
+
+import openpyxl
+from docopt import docopt
+from openpyxl.chart import LineChart, Reference
+
+doc = """
+Usage:
+  generate_latency_graph.py --latencies-log <file_name> [--num-ops <ops>]
+
+Options:
+  --latencies-log <name>                Name of the file, where the latencies are grepped from ceph OSD log
+                                        -> grep -a dequeue_op.*latency ceph-osd.log > latencies.log
+  ----num-ops <num>                     Top N latencies to be collected for the graph
+"""
+
+
+class Op(object):
+    def __init__(self, line):
+        self.lat = float(re.search(r"latency (\d+.\\d+)", line).group(1))
+        self.line = line
+        time_format = "%Y-%m-%d %H:%M:%S.%f"
+        self.time = datetime.strptime(line[:23], time_format)
+
+
+def run(args):
+    logfile = args["--latencies-log"]
+    num_ops = int(args.get("--num-ops", 10000))
+    ops = []
+    top_ops = []
+
+    with open(logfile) as f:
+        for line in f.readlines():
+            ops.append(Op(line))
+    ops.sort(key=lambda x: x.time)
+    print(f"{num_ops} longest requests:")
+    for i in range(min(num_ops, len(ops))):
+        top_ops.append((ops[i].lat, ops[i].time, ops[i].line))
+    top_ops.sort(key=lambda x: x[1])
+    # Creating workbook and adding data to it
+    wb = openpyxl.Workbook()
+    sheet = wb.active
+    text = f"Operations from Timestamp :{ops[0].time} - {ops[-1].time}"
+    sheet.append([text])
+    for val in top_ops:
+        sheet.append([val[0], val[1]])
+
+    max_row = sheet.max_row  # if sheet.max_row < 100 else 100
+    values = Reference(sheet, min_col=1, min_row=2, max_col=1, max_row=max_row)
+    # Create object of LineChart class
+    chart = LineChart()
+    chart.add_data(values)
+    # set the title of the chart
+    chart.title = f" Latencies {text}"
+    chart.x_axis.title = " Time progression ----> "
+    chart.y_axis.title = " Time in sec "
+    sheet.add_chart(chart, "E2")
+
+    # save the file
+    fname = f"{sys.argv[1]}.xlsx"
+    wb.save(fname)
+    print("Done!")
+
+
+if __name__ == "__main__":
+    args = docopt(doc)
+    try:
+        run(args)
+    except Exception as err:
+        print(
+            f"Exception hit while generating graph for the latencies provided.\n error : {err} "
+        )
+        exit(1)