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author | Victor Stinner <vstinner@python.org> | 2019-10-03 08:53:17 (GMT) |
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committer | GitHub <noreply@github.com> | 2019-10-03 08:53:17 (GMT) |
commit | c65119d5bfded03f80a9805889391b66fa7bf551 (patch) | |
tree | ff8f229b25ce5d1052c46f34ac181bd5138b749c /Lib/test | |
parent | 3e04cd268ee9a57f95dc78d8974b21a6fac3f666 (diff) | |
download | cpython-c65119d5bfded03f80a9805889391b66fa7bf551.zip cpython-c65119d5bfded03f80a9805889391b66fa7bf551.tar.gz cpython-c65119d5bfded03f80a9805889391b66fa7bf551.tar.bz2 |
bpo-36670: Enhance regrtest WindowsLoadTracker (GH-16553)
The last line is now passed to the parser even if it does not end
with a newline, but only if it's a valid value.
Diffstat (limited to 'Lib/test')
-rw-r--r-- | Lib/test/libregrtest/win_utils.py | 68 |
1 files changed, 42 insertions, 26 deletions
diff --git a/Lib/test/libregrtest/win_utils.py b/Lib/test/libregrtest/win_utils.py index f802980..0b73a94 100644 --- a/Lib/test/libregrtest/win_utils.py +++ b/Lib/test/libregrtest/win_utils.py @@ -14,7 +14,7 @@ BUFSIZE = 8192 LOAD_FACTOR_1 = 0.9200444146293232478931553241 # Seconds per measurement -SAMPLING_INTERVAL = 5 +SAMPLING_INTERVAL = 1 # Windows registry subkey of HKEY_LOCAL_MACHINE where the counter names # of typeperf are registered COUNTER_REGISTRY_KEY = (r"SOFTWARE\Microsoft\Windows NT\CurrentVersion" @@ -32,7 +32,7 @@ class WindowsLoadTracker(): def __init__(self): self.load = 0.0 self.counter_name = '' - self._buffer = b'' + self._buffer = '' self.popen = None self.start() @@ -95,44 +95,60 @@ class WindowsLoadTracker(): def __del__(self): self.close() - def read_output(self): + def _parse_line(self, line): + # typeperf outputs in a CSV format like this: + # "07/19/2018 01:32:26.605","3.000000" + # (date, process queue length) + tokens = line.split(',') + if len(tokens) != 2: + raise ValueError + + value = tokens[1] + if not value.startswith('"') or not value.endswith('"'): + raise ValueError + value = value[1:-1] + return float(value) + + def read_lines(self): overlapped, _ = _winapi.ReadFile(self.pipe, BUFSIZE, True) bytes_read, res = overlapped.GetOverlappedResult(False) if res != 0: - return - - # self._buffer stores an incomplete line - output = self._buffer + overlapped.getbuffer() - output, _, self._buffer = output.rpartition(b'\n') - return output.decode('oem', 'replace') + return () + + output = overlapped.getbuffer() + output = output.decode('oem', 'replace') + output = self._buffer + output + lines = output.splitlines(True) + + # bpo-36670: typeperf only writes a newline *before* writing a value, + # not after. Sometimes, the written line in incomplete (ex: only + # timestamp, without the process queue length). Only pass the last line + # to the parser if it's a valid value, otherwise store it in + # self._buffer. + try: + self._parse_line(lines[-1]) + except ValueError: + self._buffer = lines.pop(-1) + else: + self._buffer = '' + + return lines def getloadavg(self): - typeperf_output = self.read_output() - # Nothing to update, just return the current load - if not typeperf_output: - return self.load + for line in self.read_lines(): + line = line.rstrip() - # Process the backlog of load values - for line in typeperf_output.splitlines(): # Ignore the initial header: # "(PDH-CSV 4.0)","\\\\WIN\\System\\Processor Queue Length" - if '\\\\' in line: + if 'PDH-CSV' in line: continue # Ignore blank lines - if not line.strip(): + if not line: continue - # typeperf outputs in a CSV format like this: - # "07/19/2018 01:32:26.605","3.000000" - # (date, process queue length) try: - tokens = line.split(',') - if len(tokens) != 2: - raise ValueError - - value = tokens[1].replace('"', '') - load = float(value) + load = self._parse_line(line) except ValueError: print_warning("Failed to parse typeperf output: %a" % line) continue |