Mercurial > hg
view tests/killdaemons.py @ 51681:522b4d729e89
mmap: populate the mapping by default
Without pre-population, accessing all data through a mmap can result in many
pagefault, reducing performance significantly. If the mmap is prepopulated, the
performance can no longer get slower than a full read.
(See benchmark number below)
In some cases were very few data is read, prepopulating can be overkill and
slower than populating on access (through page fault). So that behavior can be
controlled when the caller can pre-determine the best behavior.
(See benchmark number below)
In addition, testing with populating in a secondary thread yield great result
combining the best of each approach. This might be implemented in later
changesets.
In all cases, using mmap has a great effect on memory usage when many processes
run in parallel on the same machine.
### Benchmarks
# What did I run
A couple of month back I ran a large benchmark campaign to assess the impact of
various approach for using mmap with the revlog (and other files), it
highlighted a few benchmarks that capture the impact of the changes well. So to
validate this change I checked the following:
- log command displaying various revisions
(read the changelog index)
- log command displaying the patch of listed revisions
(read the changelog index, the manifest index and a few files indexes)
- unbundling a few revisions
(read and write changelog, manifest and few files indexes, and walk the graph
to update some cache)
- pushing a few revisions
(read and write changelog, manifest and few files indexes, walk the graph to
update some cache, performs various accesses locally and remotely during
discovery)
Benchmarks were run using the default module policy (c+py) and the rust one. No
significant difference were found between the two implementation, so we will
present result using the default policy (unless otherwise specified).
I ran them on a few repositories :
- mercurial: a "public changeset only" copy of mercurial from 2018-08-01 using
zstd compression and sparse-revlog
- pypy: a copy of pypy from 2018-08-01 using zstd compression and sparse-revlog
- netbeans: a copy of netbeans from 2018-08-01 using zstd compression and
sparse-revlog
- mozilla-try: a copy of mozilla-try from 2019-02-18 using zstd compression and
sparse-revlog
- mozilla-try persistent-nodemap: Same as the above but with a persistent
nodemap. Used for the log --patch benchmark only
# Results
For the smaller repositories (mercurial, pypy), the impact of mmap is almost
imperceptible, other cost dominating the operation. The impact of prepopulating
is undiscernible in the benchmark we ran.
For larger repositories the benchmark support explanation given above:
On netbeans, the log can be about 1% faster without repopulation (for a
difference < 100ms) but unbundle becomes a bit slower, even when small.
### data-env-vars.name = netbeans-2018-08-01-zstd-sparse-revlog
# benchmark.name = hg.command.unbundle
# benchmark.variants.issue6528 = disabled
# benchmark.variants.reuse-external-delta-parent = yes
# benchmark.variants.revs = any-1-extra-rev
# benchmark.variants.source = unbundle
# benchmark.variants.verbosity = quiet
with-populate: 0.240157
no-populate: 0.265087 (+10.38%, +0.02)
# benchmark.variants.revs = any-100-extra-rev
with-populate: 1.459518
no-populate: 1.481290 (+1.49%, +0.02)
## benchmark.name = hg.command.push
# benchmark.variants.explicit-rev = none
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = yes
# benchmark.variants.revs = any-1-extra-rev
with-populate: 0.771919
no-populate: 0.792025 (+2.60%, +0.02)
# benchmark.variants.revs = any-100-extra-rev
with-populate: 1.459518
no-populate: 1.481290 (+1.49%, +0.02)
For mozilla-try, the "slow down" from pre-populate for small `hg log` is more
visible, but still small in absolute time. (using rust value for the persistent
nodemap value to be relevant).
### data-env-vars.name = mozilla-try-2019-02-18-ds2-pnm
# benchmark.name = hg.command.log
# bin-env-vars.hg.flavor = rust
# benchmark.variants.patch = yes
# benchmark.variants.limit-rev = 1
with-populate: 0.237813
no-populate: 0.229452 (-3.52%, -0.01)
# benchmark.variants.limit-rev = 10
# benchmark.variants.patch = yes
with-populate: 1.213578
no-populate: 1.205189
### data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
# benchmark.variants.limit-rev = 1000
# benchmark.variants.patch = no
# benchmark.variants.rev = tip
with-populate: 0.198607
no-populate: 0.195038 (-1.80%, -0.00)
However pre-populating provide a significant boost on more complex operations
like unbundle or push:
### data-env-vars.name = mozilla-try-2019-02-18-zstd-sparse-revlog
# benchmark.name = hg.command.push
# benchmark.variants.explicit-rev = none
# benchmark.variants.issue6528 = disabled
# benchmark.variants.protocol = ssh
# benchmark.variants.reuse-external-delta-parent = yes
# benchmark.variants.revs = any-1-extra-rev
with-populate: 4.798632
no-populate: 4.953295 (+3.22%, +0.15)
# benchmark.variants.revs = any-100-extra-rev
with-populate: 4.903618
no-populate: 5.014963 (+2.27%, +0.11)
## benchmark.name = hg.command.unbundle
# benchmark.variants.revs = any-1-extra-rev
with-populate: 1.423411
no-populate: 1.585365 (+11.38%, +0.16)
# benchmark.variants.revs = any-100-extra-rev
with-populate: 1.537909
no-populate: 1.688489 (+9.79%, +0.15)
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Thu, 11 Apr 2024 00:02:07 +0200 |
parents | d54b213c4380 |
children | 493034cc3265 |
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#!/usr/bin/env python3 import os import signal import sys import time if os.name == 'nt': import ctypes _BOOL = ctypes.c_long _DWORD = ctypes.c_ulong _UINT = ctypes.c_uint _HANDLE = ctypes.c_void_p ctypes.windll.kernel32.CloseHandle.argtypes = [_HANDLE] ctypes.windll.kernel32.CloseHandle.restype = _BOOL ctypes.windll.kernel32.GetLastError.argtypes = [] ctypes.windll.kernel32.GetLastError.restype = _DWORD ctypes.windll.kernel32.OpenProcess.argtypes = [_DWORD, _BOOL, _DWORD] ctypes.windll.kernel32.OpenProcess.restype = _HANDLE ctypes.windll.kernel32.TerminateProcess.argtypes = [_HANDLE, _UINT] ctypes.windll.kernel32.TerminateProcess.restype = _BOOL ctypes.windll.kernel32.WaitForSingleObject.argtypes = [_HANDLE, _DWORD] ctypes.windll.kernel32.WaitForSingleObject.restype = _DWORD def _check(ret, expectederr=None): if ret == 0: winerrno = ctypes.GetLastError() if winerrno == expectederr: return True raise ctypes.WinError(winerrno) def kill(pid, logfn, tryhard=True): logfn('# Killing daemon process %d' % pid) PROCESS_TERMINATE = 1 PROCESS_QUERY_INFORMATION = 0x400 SYNCHRONIZE = 0x00100000 WAIT_OBJECT_0 = 0 WAIT_TIMEOUT = 258 WAIT_FAILED = _DWORD(0xFFFFFFFF).value handle = ctypes.windll.kernel32.OpenProcess( PROCESS_TERMINATE | SYNCHRONIZE | PROCESS_QUERY_INFORMATION, False, pid, ) if handle is None: _check(0, 87) # err 87 when process not found return # process not found, already finished try: r = ctypes.windll.kernel32.WaitForSingleObject(handle, 100) if r == WAIT_OBJECT_0: pass # terminated, but process handle still available elif r == WAIT_TIMEOUT: _check(ctypes.windll.kernel32.TerminateProcess(handle, -1)) elif r == WAIT_FAILED: _check(0) # err stored in GetLastError() # TODO?: forcefully kill when timeout # and ?shorter waiting time? when tryhard==True r = ctypes.windll.kernel32.WaitForSingleObject(handle, 100) # timeout = 100 ms if r == WAIT_OBJECT_0: pass # process is terminated elif r == WAIT_TIMEOUT: logfn('# Daemon process %d is stuck') elif r == WAIT_FAILED: _check(0) # err stored in GetLastError() except: # re-raises ctypes.windll.kernel32.CloseHandle(handle) # no _check, keep error raise _check(ctypes.windll.kernel32.CloseHandle(handle)) else: def kill(pid, logfn, tryhard=True): try: os.kill(pid, 0) logfn('# Killing daemon process %d' % pid) os.kill(pid, signal.SIGTERM) if tryhard: for i in range(10): time.sleep(0.05) os.kill(pid, 0) else: time.sleep(0.1) os.kill(pid, 0) logfn('# Daemon process %d is stuck - really killing it' % pid) os.kill(pid, signal.SIGKILL) except ProcessLookupError: pass def killdaemons(pidfile, tryhard=True, remove=False, logfn=None): if not logfn: logfn = lambda s: s # Kill off any leftover daemon processes try: pids = [] with open(pidfile) as fp: for line in fp: try: pid = int(line) if pid <= 0: raise ValueError except ValueError: logfn( '# Not killing daemon process %s - invalid pid' % line.rstrip() ) continue pids.append(pid) for pid in pids: kill(pid, logfn, tryhard) if remove: os.unlink(pidfile) except IOError: pass if __name__ == '__main__': if len(sys.argv) > 1: (path,) = sys.argv[1:] else: path = os.environ["DAEMON_PIDS"] killdaemons(path, remove=True)