diff options
Diffstat (limited to 'Lib/test/support.py')
| -rw-r--r-- | Lib/test/support.py | 109 |
1 files changed, 66 insertions, 43 deletions
diff --git a/Lib/test/support.py b/Lib/test/support.py index 62ad606..cce04aa 100644 --- a/Lib/test/support.py +++ b/Lib/test/support.py @@ -23,6 +23,7 @@ import time import sysconfig import fnmatch import logging.handlers +import struct try: import _thread, threading @@ -34,6 +35,10 @@ try: except ImportError: multiprocessing = None +try: + import faulthandler +except ImportError: + faulthandler = None try: import zlib @@ -1133,41 +1138,66 @@ def set_memlimit(limit): raise ValueError('Memory limit %r too low to be useful' % (limit,)) max_memuse = memlimit -def _memory_watchdog(start_evt, finish_evt, period=10.0): - """A function which periodically watches the process' memory consumption +class _MemoryWatchdog: + """An object which periodically watches the process' memory consumption and prints it out. """ - # XXX: because of the GIL, and because the very long operations tested - # in most bigmem tests are uninterruptible, the loop below gets woken up - # much less often than expected. - # The polling code should be rewritten in raw C, without holding the GIL, - # and push results onto an anonymous pipe. - try: - page_size = os.sysconf('SC_PAGESIZE') - except (ValueError, AttributeError): + + def __init__(self): + self.procfile = '/proc/{pid}/statm'.format(pid=os.getpid()) + self.started = False + self.thread = None try: - page_size = os.sysconf('SC_PAGE_SIZE') + self.page_size = os.sysconf('SC_PAGESIZE') except (ValueError, AttributeError): - page_size = 4096 - procfile = '/proc/{pid}/statm'.format(pid=os.getpid()) - try: - f = open(procfile, 'rb') - except IOError as e: - warnings.warn('/proc not available for stats: {}'.format(e), - RuntimeWarning) - sys.stderr.flush() - return - with f: - start_evt.set() - old_data = -1 - while not finish_evt.wait(period): - f.seek(0) - statm = f.read().decode('ascii') - data = int(statm.split()[5]) - if data != old_data: - old_data = data + try: + self.page_size = os.sysconf('SC_PAGE_SIZE') + except (ValueError, AttributeError): + self.page_size = 4096 + + def consumer(self, fd): + HEADER = "l" + header_size = struct.calcsize(HEADER) + try: + while True: + header = os.read(fd, header_size) + if len(header) < header_size: + # Pipe closed on other end + break + data_len, = struct.unpack(HEADER, header) + data = os.read(fd, data_len) + statm = data.decode('ascii') + data = int(statm.split()[5]) print(" ... process data size: {data:.1f}G" - .format(data=data * page_size / (1024 ** 3))) + .format(data=data * self.page_size / (1024 ** 3))) + finally: + os.close(fd) + + def start(self): + if not faulthandler or not hasattr(faulthandler, '_file_watchdog'): + return + try: + rfd = os.open(self.procfile, os.O_RDONLY) + except OSError as e: + warnings.warn('/proc not available for stats: {}'.format(e), + RuntimeWarning) + sys.stderr.flush() + return + pipe_fd, wfd = os.pipe() + # _file_watchdog() doesn't take the GIL in its child thread, and + # therefore collects statistics timely + faulthandler._file_watchdog(rfd, wfd, 3.0) + self.started = True + self.thread = threading.Thread(target=self.consumer, args=(pipe_fd,)) + self.thread.daemon = True + self.thread.start() + + def stop(self): + if not self.started: + return + faulthandler._cancel_file_watchdog() + self.thread.join() + def bigmemtest(size, memuse, dry_run=True): """Decorator for bigmem tests. @@ -1194,27 +1224,20 @@ def bigmemtest(size, memuse, dry_run=True): "not enough memory: %.1fG minimum needed" % (size * memuse / (1024 ** 3))) - if real_max_memuse and verbose and threading: + if real_max_memuse and verbose and faulthandler and threading: print() print(" ... expected peak memory use: {peak:.1f}G" .format(peak=size * memuse / (1024 ** 3))) - sys.stdout.flush() - start_evt = threading.Event() - finish_evt = threading.Event() - t = threading.Thread(target=_memory_watchdog, - args=(start_evt, finish_evt, 0.5)) - t.daemon = True - t.start() - start_evt.set() + watchdog = _MemoryWatchdog() + watchdog.start() else: - t = None + watchdog = None try: return f(self, maxsize) finally: - if t: - finish_evt.set() - t.join() + if watchdog: + watchdog.stop() wrapper.size = size wrapper.memuse = memuse |