largefiles: don't verify largefile hashes on servers when processing statlfile
When changesets referencing largefiles are pushed then the corresponding
largefiles will be pushed too - unless the target already has them. The client
will use statlfile to make sure it only sends largefiles that the target
doesn't have. The server would however on every statlfile check that the
content of the largefile had the expected hash. What should be cheap thus
became an expensive operation that trashed the disk and the cache.
Largefile hashes are already checked by putlfile before being stored on the
server. A server should thus be able to keep its largefile store free of
errors - even more than it can keep revlogs free of errors. Verification should
happen when running 'hg verify' locally on the server. Rehashing every
largefile on every remote stat is too expensive.
Clients will also stat lfiles before downloading them. When the server verified
the hash in stat it meant that it had to read the file twice to serve it.
With this change the server will assume its own hashes are ok without checking
them on every statlfile.
Some consequences of this change:
- in case of server side corruption the problem will be detected by the
existing check on the client side - not on server side
- clients that could upload an uncorrupted largefile when pushing will no
longer magically heal the server (and break hardlinks) - a client will now
only upload its uncorrupted files after the corrupted file has been removed
on the server side
- client side verify will no longer report corruption in files it doesn't have
(Issue3123 discussed related problems - and how they have been fixed.)
# error.py - Mercurial exceptions
#
# Copyright 2005-2008 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Mercurial exceptions.
This allows us to catch exceptions at higher levels without forcing
imports.
"""
# Do not import anything here, please
class RevlogError(Exception):
pass
class LookupError(RevlogError, KeyError):
def __init__(self, name, index, message):
self.name = name
if isinstance(name, str) and len(name) == 20:
from node import short
name = short(name)
RevlogError.__init__(self, '%s@%s: %s' % (index, name, message))
def __str__(self):
return RevlogError.__str__(self)
class CommandError(Exception):
"""Exception raised on errors in parsing the command line."""
class Abort(Exception):
"""Raised if a command needs to print an error and exit."""
def __init__(self, *args, **kw):
Exception.__init__(self, *args)
self.hint = kw.get('hint')
class ConfigError(Abort):
'Exception raised when parsing config files'
class OutOfBandError(Exception):
'Exception raised when a remote repo reports failure'
class ParseError(Exception):
'Exception raised when parsing config files (msg[, pos])'
class RepoError(Exception):
def __init__(self, *args, **kw):
Exception.__init__(self, *args)
self.hint = kw.get('hint')
class RepoLookupError(RepoError):
pass
class CapabilityError(RepoError):
pass
class RequirementError(RepoError):
"""Exception raised if .hg/requires has an unknown entry."""
pass
class LockError(IOError):
def __init__(self, errno, strerror, filename, desc):
IOError.__init__(self, errno, strerror, filename)
self.desc = desc
class LockHeld(LockError):
def __init__(self, errno, filename, desc, locker):
LockError.__init__(self, errno, 'Lock held', filename, desc)
self.locker = locker
class LockUnavailable(LockError):
pass
class ResponseError(Exception):
"""Raised to print an error with part of output and exit."""
class UnknownCommand(Exception):
"""Exception raised if command is not in the command table."""
class AmbiguousCommand(Exception):
"""Exception raised if command shortcut matches more than one command."""
# derived from KeyboardInterrupt to simplify some breakout code
class SignalInterrupt(KeyboardInterrupt):
"""Exception raised on SIGTERM and SIGHUP."""
class SignatureError(Exception):
pass