##// END OF EJS Templates
chg: handle EOF reading data block...
chg: handle EOF reading data block We recently discovered a case in production that chg uses 100% CPU and is trying to read data forever: recvfrom(4, "", 1814012019, 0, NULL, NULL) = 0 Using gdb, apparently readchannel() got wrong data. It was reading in an infinite loop because rsize == 0 does not exit the loop, while the server process had ended. (gdb) bt #0 ... in recv () at /lib64/libc.so.6 #1 ... in readchannel (...) at /usr/include/bits/socket2.h:45 #2 ... in readchannel (hgc=...) at hgclient.c:129 #3 ... in handleresponse (hgc=...) at hgclient.c:255 #4 ... in hgc_runcommand (hgc=..., args=<optimized>, argsize=<optimized>) #5 ... in main (argc=...486922636, argv=..., envp=...) at chg.c:661 (gdb) frame 2 (gdb) p *hgc $1 = {sockfd = 4, pid = 381152, ctx = {ch = 108 'l', data = 0x7fb05164f010 "st):\nTraceback (most recent call last):\n" "Traceback (most recent call last):\ne", maxdatasize = 1814065152," " datasize = 1814064225}, capflags = 16131} This patch addresses the infinite loop issue by detecting continuously empty responses and abort in that case. Note that datasize can be translated to ['l', ' ', 'l', 'a']. Concatenate datasize and data, it forms part of "Traceback (most recent call last):". This may indicate a server-side channeledoutput issue. If it is a race condition, we may want to use flock to protect the channels.

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remotestore.py
133 lines | 4.9 KiB | text/x-python | PythonLexer
# Copyright 2010-2011 Fog Creek Software
# Copyright 2010-2011 Unity Technologies
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
'''remote largefile store; the base class for wirestore'''
from __future__ import absolute_import
from mercurial.i18n import _
from mercurial import (
error,
util,
wireproto,
)
from . import (
basestore,
lfutil,
localstore,
)
urlerr = util.urlerr
urlreq = util.urlreq
class remotestore(basestore.basestore):
'''a largefile store accessed over a network'''
def __init__(self, ui, repo, url):
super(remotestore, self).__init__(ui, repo, url)
self._lstore = localstore.localstore(self.ui, self.repo, self.repo)
def put(self, source, hash):
if self.sendfile(source, hash):
raise error.Abort(
_('remotestore: could not put %s to remote store %s')
% (source, util.hidepassword(self.url)))
self.ui.debug(
_('remotestore: put %s to remote store %s\n')
% (source, util.hidepassword(self.url)))
def exists(self, hashes):
return dict((h, s == 0) for (h, s) in # dict-from-generator
self._stat(hashes).iteritems())
def sendfile(self, filename, hash):
self.ui.debug('remotestore: sendfile(%s, %s)\n' % (filename, hash))
fd = None
try:
fd = lfutil.httpsendfile(self.ui, filename)
return self._put(hash, fd)
except IOError as e:
raise error.Abort(
_('remotestore: could not open file %s: %s')
% (filename, str(e)))
finally:
if fd:
fd.close()
def _getfile(self, tmpfile, filename, hash):
try:
chunks = self._get(hash)
except urlerr.httperror as e:
# 401s get converted to error.Aborts; everything else is fine being
# turned into a StoreError
raise basestore.StoreError(filename, hash, self.url, str(e))
except urlerr.urlerror as e:
# This usually indicates a connection problem, so don't
# keep trying with the other files... they will probably
# all fail too.
raise error.Abort('%s: %s' %
(util.hidepassword(self.url), e.reason))
except IOError as e:
raise basestore.StoreError(filename, hash, self.url, str(e))
return lfutil.copyandhash(chunks, tmpfile)
def _hashesavailablelocally(self, hashes):
existslocallymap = self._lstore.exists(hashes)
localhashes = [hash for hash in hashes if existslocallymap[hash]]
return localhashes
def _verifyfiles(self, contents, filestocheck):
failed = False
expectedhashes = [expectedhash
for cset, filename, expectedhash in filestocheck]
localhashes = self._hashesavailablelocally(expectedhashes)
stats = self._stat([expectedhash for expectedhash in expectedhashes
if expectedhash not in localhashes])
for cset, filename, expectedhash in filestocheck:
if expectedhash in localhashes:
filetocheck = (cset, filename, expectedhash)
verifyresult = self._lstore._verifyfiles(contents,
[filetocheck])
if verifyresult:
failed = True
else:
stat = stats[expectedhash]
if stat:
if stat == 1:
self.ui.warn(
_('changeset %s: %s: contents differ\n')
% (cset, filename))
failed = True
elif stat == 2:
self.ui.warn(
_('changeset %s: %s missing\n')
% (cset, filename))
failed = True
else:
raise RuntimeError('verify failed: unexpected response '
'from statlfile (%r)' % stat)
return failed
def batch(self):
'''Support for remote batching.'''
return wireproto.remotebatch(self)
def _put(self, hash, fd):
'''Put file with the given hash in the remote store.'''
raise NotImplementedError('abstract method')
def _get(self, hash):
'''Get file with the given hash from the remote store.'''
raise NotImplementedError('abstract method')
def _stat(self, hashes):
'''Get information about availability of files specified by
hashes in the remote store. Return dictionary mapping hashes
to return code where 0 means that file is available, other
values if not.'''
raise NotImplementedError('abstract method')