Added cf-profile.py script for processing profiling output

Changelog: Title
Signed-off-by: Victor Moene <[email protected]>

Author: victormlg

contrib/cf-profile/cf-profile.py

@@ -0,0 +1,149 @@
+from argparse import ArgumentParser
+import sys
+import json
+import re
+from collections import defaultdict
+
+"""
+This script parses profiling output from cf-agent and lists policy bundles, promises, and functions sorted by execution time.
+
+Usage:
+    $ sudo /var/cfengine/cf-agent -Kp > profiling_output.json
+    $ cat profiling_output.json | python3 cf-profile.py --bundles --promises --functions
+
+To generate a flamegraph:
+    $ cat profiling_output.json | python3 cf-profile.py --flamegraph callstack.txt
+    $ ./flamegraph.pl callstack.txt > flamegraph.svg
+"""
+
+
+def parse_args():
+    parser = ArgumentParser()
+
+    parser.add_argument("--top", type=int, default=10)
+    parser.add_argument("--bundles", action="store_true")
+    parser.add_argument("--promises", action="store_true")
+    parser.add_argument("--functions", action="store_true")
+    parser.add_argument("--flamegraph", type=str, default="callstack.txt")
+
+    return parser.parse_args()
+
+
+def format_elapsed_time(elapsed_ns):
+    elapsed_ms = float(elapsed_ns) / 1e6
+
+    if elapsed_ms < 1000:
+        return "%.2f ms" % elapsed_ms
+    elif elapsed_ms < 60000:
+        elapsed_s = elapsed_ms / 1000.0
+        return "%.2fs" % elapsed_s
+    else:
+        elapsed_s = elapsed_ms / 1000.0
+        minutes = int(elapsed_s // 60)
+        seconds = int(elapsed_s % 60)
+        return "%dm%ds" % (minutes, seconds)
+
+
+def format_label(component, event_type, ns, name):
+    if component == "function":
+        return "%s %s" % (component, name)
+    elif event_type == "methods":
+        return "bundle invocation"
+    elif component == "promise":
+        return "%s %s" % (component, event_type)
+    else:
+        return "%s %s %s:%s" % (component, event_type, ns, name)
+
+
+def format_columns(events, top):
+
+    labels = []
+
+    for event in events[:top]:
+        label = format_label(
+            event["component"], event["type"], event["namespace"], event["name"]
+        )
+        location = "%s:%s" % (event["source"], event["offset"]["line"])
+        time = format_elapsed_time(event["elapsed"])
+
+        labels.append((label, location, time))
+
+    return labels
+
+
+def get_max_column_lengths(lines, indent=4):
+
+    max_type, max_location, max_time = 0, 0, 0
+
+    for label, location, time_ms in lines:
+        max_type = max(max_type, len(label))
+        max_location = max(max_location, len(location))
+        max_time = max(max_time, len(time_ms))
+
+    return max_type + indent, max_location + indent, max_time + indent
+
+
+def profile(events, args):
+
+    filter = defaultdict(list)
+
+    if args.bundles:
+        filter["component"].append("bundle")
+        filter["type"].append("methods")
+
+    if args.promises:
+        filter["type"] += list(
+            set(
+                event["type"]
+                for event in events
+                if event["component"] == "promise" and event["type"] != "methods"
+            )
+        )
+
+    if args.functions:
+        filter["component"].append("function")
+
+    print(filter)
+
+    # filter events
+    if filter is not None:
+        events = [
+            event
+            for field in filter.keys()
+            for event in events
+            if event[field] in filter[field]
+        ]
+
+    # sort events
+    events = sorted(events, key=lambda x: x["elapsed"], reverse=True)
+
+    lines = format_columns(events, args.top)
+    line_format = "%-{}s %-{}s %{}s".format(*get_max_column_lengths(lines))
+
+    # print top k filtered events
+    print(line_format % ("Type", "Location", "Time"))
+    for label, location, time_ms in lines:
+        print(line_format % (label, location, time_ms))
+
+
+def generate_callstacks(data, stack_path):
+
+    with open(stack_path, "w") as f:
+        for event in data:
+            f.write("%s %d\n" % (event["callstack"], event["elapsed"]))
+
+
+def main():
+    args = parse_args()
+    m = re.search(r"\[[.\s\S]*\]", sys.stdin.read())
+    data = json.loads(m.group(0))
+
+    if any([args.bundles, args.functions, args.promises]):
+        profile(data, args)
+
+    if args.flamegraph:
+        generate_callstacks(data, args.flamegraph)
+
+
+if __name__ == "__main__":
+    main()