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|
import os
import sys
import time
import stat
import random
import signal
import json
import logging
import socket
import string
import errno
from shutil import copyfileobj
from errno import ENOENT, ENODATA, EPIPE, EEXIST, errorcode
from threading import currentThread, Condition, Lock
from datetime import datetime
from libcxattr import Xattr
from gconf import gconf
from tempfile import mkdtemp, NamedTemporaryFile
from syncdutils import FreeObject, Thread, GsyncdError, boolify, escape, \
unescape, select, gauxpfx, md5hex, selfkill, entry2pb, \
lstat, errno_wrap, update_file
URXTIME = (-1, 0)
# Utility functions to help us to get to closer proximity
# of the DRY principle (no, don't look for elevated or
# perspectivistic things here)
def _xtime_now():
t = time.time()
sec = int(t)
nsec = int((t - sec) * 1000000)
return (sec, nsec)
def _volinfo_hook_relax_foreign(self):
volinfo_sys = self.get_sys_volinfo()
fgn_vi = volinfo_sys[self.KFGN]
if fgn_vi:
expiry = fgn_vi['timeout'] - int(time.time()) + 1
logging.info('foreign volume info found, waiting %d sec for expiry' % \
expiry)
time.sleep(expiry)
volinfo_sys = self.get_sys_volinfo()
return volinfo_sys
# The API!
def gmaster_builder(excrawl=None):
"""produce the GMaster class variant corresponding
to sync mode"""
this = sys.modules[__name__]
modemixin = gconf.special_sync_mode
if not modemixin:
modemixin = 'normal'
changemixin = isinstance(excrawl, str) and excrawl or gconf.change_detector
logging.info('setting up %s change detection mode' % changemixin)
modemixin = getattr(this, modemixin.capitalize() + 'Mixin')
crawlmixin = getattr(this, 'GMaster' + changemixin.capitalize() + 'Mixin')
sendmarkmixin = boolify(gconf.use_rsync_xattrs) and SendmarkRsyncMixin or SendmarkNormalMixin
purgemixin = boolify(gconf.ignore_deletes) and PurgeNoopMixin or PurgeNormalMixin
syncengine = boolify(gconf.use_tarssh) and TarSSHEngine or RsyncEngine
class _GMaster(crawlmixin, modemixin, sendmarkmixin, purgemixin, syncengine):
pass
return _GMaster
# Mixin classes that implement the data format
# and logic particularities of the certain
# sync modes
class NormalMixin(object):
"""normal geo-rep behavior"""
minus_infinity = URXTIME
# following staticmethods ideally would be
# methods of an xtime object (in particular,
# implementing the hooks needed for comparison
# operators), but at this point we don't yet
# have a dedicated xtime class
@staticmethod
def serialize_xtime(xt):
return "%d.%d" % tuple(xt)
@staticmethod
def deserialize_xtime(xt):
return tuple(int(x) for x in xt.split("."))
@staticmethod
def native_xtime(xt):
return xt
@staticmethod
def xtime_geq(xt0, xt1):
return xt0 >= xt1
def make_xtime_opts(self, is_master, opts):
if not 'create' in opts:
opts['create'] = is_master
if not 'default_xtime' in opts:
opts['default_xtime'] = URXTIME
def xtime_low(self, rsc, path, **opts):
if rsc == self.master:
xt = rsc.server.xtime(path, self.uuid)
else:
xt = rsc.server.stime(path, self.uuid)
if isinstance(xt, int) and xt == ENODATA:
xt = rsc.server.xtime(path, self.uuid)
if not isinstance(xt, int):
self.slave.server.set_stime(path, self.uuid, xt)
if isinstance(xt, int) and xt != ENODATA:
return xt
if xt == ENODATA or xt < self.volmark:
if opts['create']:
xt = _xtime_now()
rsc.server.aggregated.set_xtime(path, self.uuid, xt)
else:
xt = opts['default_xtime']
return xt
def keepalive_payload_hook(self, timo, gap):
# first grab a reference as self.volinfo
# can be changed in main thread
vi = self.volinfo
if vi:
# then have a private copy which we can mod
vi = vi.copy()
vi['timeout'] = int(time.time()) + timo
else:
# send keep-alives more frequently to
# avoid a delay in announcing our volume info
# to slave if it becomes established in the
# meantime
gap = min(10, gap)
return (vi, gap)
def volinfo_hook(self):
return self.get_sys_volinfo()
def xtime_reversion_hook(self, path, xtl, xtr):
if xtr > xtl:
raise GsyncdError("timestamp corruption for " + path)
def need_sync(self, e, xte, xtrd):
return xte > xtrd
def set_slave_xtime(self, path, mark):
self.slave.server.set_stime(path, self.uuid, mark)
self.slave.server.set_xtime_remote(path, self.uuid, mark)
class PartialMixin(NormalMixin):
"""a variant tuned towards operation with a master
that has partial info of the slave (brick typically)"""
def xtime_reversion_hook(self, path, xtl, xtr):
pass
class RecoverMixin(NormalMixin):
"""a variant that differs from normal in terms
of ignoring non-indexed files"""
@staticmethod
def make_xtime_opts(is_master, opts):
if not 'create' in opts:
opts['create'] = False
if not 'default_xtime' in opts:
opts['default_xtime'] = URXTIME
def keepalive_payload_hook(self, timo, gap):
return (None, gap)
def volinfo_hook(self):
return _volinfo_hook_relax_foreign(self)
# Further mixins for certain tunable behaviors
class SendmarkNormalMixin(object):
def sendmark_regular(self, *a, **kw):
return self.sendmark(*a, **kw)
class SendmarkRsyncMixin(object):
def sendmark_regular(self, *a, **kw):
pass
class PurgeNormalMixin(object):
def purge_missing(self, path, names):
self.slave.server.purge(path, names)
class PurgeNoopMixin(object):
def purge_missing(self, path, names):
pass
class TarSSHEngine(object):
"""Sync engine that uses tar(1) piped over ssh(1)
for data transfers. Good for lots of small files.
"""
def a_syncdata(self, files):
logging.debug('files: %s' % (files))
for f in files:
pb = self.syncer.add(f)
def regjob(se, xte, pb):
rv = pb.wait()
if rv[0]:
logging.debug('synced ' + se)
return True
else:
# stat check for file presence
st = lstat(se)
if isinstance(st, int):
return True
logging.warn('tar+ssh: %s [errcode: %d]' % (se, rv[1]))
self.add_job(self.FLAT_DIR_HIERARCHY, 'reg', regjob, f, None, pb)
def syncdata_wait(self):
if self.wait(self.FLAT_DIR_HIERARCHY, None):
return True
def syncdata(self, files):
self.a_syncdata(files)
self.syncdata_wait()
class RsyncEngine(object):
"""Sync engine that uses rsync(1) for data transfers"""
def a_syncdata(self, files):
logging.debug('files: %s' % (files))
for f in files:
logging.debug('candidate for syncing %s' % f)
pb = self.syncer.add(f)
def regjob(se, xte, pb):
rv = pb.wait()
if rv[0]:
logging.debug('synced ' + se)
return True
else:
if rv[1] in [23, 24]:
# stat to check if the file exist
st = lstat(se)
if isinstance(st, int):
# file got unlinked in the interim
return True
logging.warn('Rsync: %s [errcode: %d]' % (se, rv[1]))
self.add_job(self.FLAT_DIR_HIERARCHY, 'reg', regjob, f, None, pb)
def syncdata_wait(self):
if self.wait(self.FLAT_DIR_HIERARCHY, None):
return True
def syncdata(self, files):
self.a_syncdata(files)
self.syncdata_wait()
class GMasterCommon(object):
"""abstract class impementling master role"""
KFGN = 0
KNAT = 1
def get_sys_volinfo(self):
"""query volume marks on fs root
err out on multiple foreign masters
"""
fgn_vis, nat_vi = self.master.server.aggregated.foreign_volume_infos(), \
self.master.server.aggregated.native_volume_info()
fgn_vi = None
if fgn_vis:
if len(fgn_vis) > 1:
raise GsyncdError("cannot work with multiple foreign masters")
fgn_vi = fgn_vis[0]
return fgn_vi, nat_vi
@property
def uuid(self):
if self.volinfo:
return self.volinfo['uuid']
@property
def volmark(self):
if self.volinfo:
return self.volinfo['volume_mark']
def xtime(self, path, *a, **opts):
"""get amended xtime
as of amending, we can create missing xtime, or
determine a valid value if what we get is expired
(as of the volume mark expiry); way of amendig
depends on @opts and on subject of query (master
or slave).
"""
if a:
rsc = a[0]
else:
rsc = self.master
self.make_xtime_opts(rsc == self.master, opts)
return self.xtime_low(rsc, path, **opts)
def get_initial_crawl_data(self):
# while persisting only 'files_syncd' is non-zero, rest of
# the stats are nulls. lets keep it that way in case they
# are needed to be used some day...
default_data = {'files_syncd': 0,
'files_remaining': 0,
'bytes_remaining': 0,
'purges_remaining': 0,
'total_files_skipped': 0}
if getattr(gconf, 'state_detail_file', None):
try:
with open(gconf.state_detail_file, 'r+') as f:
loaded_data= json.load(f)
diff_data = set(default_data) - set (loaded_data)
if len(diff_data):
for i in diff_data:
loaded_data[i] = default_data[i]
return loaded_data
except (IOError):
ex = sys.exc_info()[1]
logging.warn ('Creating new gconf.state_detail_file.')
# Create file with initial data
try:
with open(gconf.state_detail_file, 'wb') as f:
json.dump(default_data, f)
return default_data
except:
raise
return default_data
def update_crawl_data(self):
if getattr(gconf, 'state_detail_file', None):
try:
same_dir = os.path.dirname(gconf.state_detail_file)
with NamedTemporaryFile(dir=same_dir, delete=False) as tmp:
json.dump(self.total_crawl_stats, tmp)
tmp.flush()
os.fsync(tmp.fileno())
os.rename(tmp.name, gconf.state_detail_file)
except (IOError, OSError):
raise
def __init__(self, master, slave):
self.master = master
self.slave = slave
self.jobtab = {}
if boolify(gconf.use_tarssh):
logging.info("using 'tar over ssh' as the sync engine")
self.syncer = Syncer(slave, self.slave.tarssh)
else:
logging.info("using 'rsync' as the sync engine")
# partial transfer (cf. rsync(1)), that's normal
self.syncer = Syncer(slave, self.slave.rsync, [23, 24])
# crawls vs. turns:
# - self.crawls is simply the number of crawl() invocations on root
# - one turn is a maximal consecutive sequence of crawls so that each
# crawl in it detects a change to be synced
# - self.turns is the number of turns since start
# - self.total_turns is a limit so that if self.turns reaches it, then
# we exit (for diagnostic purposes)
# so, eg., if the master fs changes unceasingly, self.turns will remain 0.
self.crawls = 0
self.turns = 0
self.total_turns = int(gconf.turns)
self.crawl_start = datetime.now()
self.lastreport = {'crawls': 0, 'turns': 0, 'time': 0}
self.total_crawl_stats = None
self.start = None
self.change_seen = None
# the actual volinfo we make use of
self.volinfo = None
self.terminate = False
self.sleep_interval = 1
self.checkpoint_thread = None
self.current_files_skipped_count = 0
self.skipped_gfid_list = []
def init_keep_alive(cls):
"""start the keep-alive thread """
timo = int(gconf.timeout or 0)
if timo > 0:
def keep_alive():
while True:
vi, gap = cls.keepalive_payload_hook(timo, timo * 0.5)
cls.slave.server.keep_alive(vi)
time.sleep(gap)
t = Thread(target=keep_alive)
t.start()
def should_crawl(cls):
return (gconf.glusterd_uuid in cls.master.server.node_uuid())
def register(self):
self.register()
def crawlwrap(self, oneshot=False):
if oneshot:
# it's important to do this during the oneshot crawl as
# for a passive gsyncd (ie. in a replicate scenario)
# the keepalive thread would keep the connection alive.
self.init_keep_alive()
# no need to maintain volinfo state machine.
# in a cascading setup, each geo-replication session is
# independent (ie. 'volume-mark' and 'xtime' are not
# propogated). This is beacuse the slave's xtime is now
# stored on the master itself. 'volume-mark' just identifies
# that we are in a cascading setup and need to enable
# 'geo-replication.ignore-pid-check' option.
volinfo_sys = self.volinfo_hook()
self.volinfo = volinfo_sys[self.KNAT]
inter_master = volinfo_sys[self.KFGN]
logging.info("%s master with volume id %s ..." % \
(inter_master and "intermediate" or "primary",
self.uuid))
gconf.configinterface.set('volume_id', self.uuid)
if self.volinfo:
if self.volinfo['retval']:
logging.warn("master cluster's info may not be valid %d" % \
self.volinfo['retval'])
self.start_checkpoint_thread()
else:
raise GsyncdError("master volinfo unavailable")
self.total_crawl_stats = self.get_initial_crawl_data()
self.lastreport['time'] = time.time()
logging.info('crawl interval: %d seconds' % self.sleep_interval)
t0 = time.time()
crawl = self.should_crawl()
while not self.terminate:
if self.start:
logging.debug("... crawl #%d done, took %.6f seconds" % \
(self.crawls, time.time() - self.start))
self.start = time.time()
should_display_info = self.start - self.lastreport['time'] >= 60
if should_display_info:
logging.info("%d crawls, %d turns",
self.crawls - self.lastreport['crawls'],
self.turns - self.lastreport['turns'])
self.lastreport.update(crawls = self.crawls,
turns = self.turns,
time = self.start)
t1 = time.time()
if int(t1 - t0) >= 60: #lets hardcode this check to 60 seconds
crawl = self.should_crawl()
t0 = t1
self.update_worker_remote_node()
if not crawl:
self.update_worker_health("Passive")
# bring up _this_ brick to the cluster stime
# which is min of cluster (but max of the replicas)
brick_stime = self.xtime('.', self.slave)
cluster_stime = self.master.server.aggregated.stime_mnt('.', '.'.join([str(self.uuid), str(gconf.slave_id)]))
logging.debug("Cluster stime: %s | Brick stime: %s" % (repr(cluster_stime), repr(brick_stime)))
if not isinstance(cluster_stime, int):
if brick_stime < cluster_stime:
self.slave.server.set_stime(self.FLAT_DIR_HIERARCHY, self.uuid, cluster_stime)
time.sleep(5)
continue
self.update_worker_health("Active")
self.crawl()
if oneshot:
return
time.sleep(self.sleep_interval)
@classmethod
def _checkpt_param(cls, chkpt, prm, xtimish=True):
"""use config backend to lookup a parameter belonging to
checkpoint @chkpt"""
cprm = gconf.configinterface.get_realtime('checkpoint_' + prm)
if not cprm:
return
chkpt_mapped, val = cprm.split(':', 1)
if unescape(chkpt_mapped) != chkpt:
return
if xtimish:
val = cls.deserialize_xtime(val)
return val
@classmethod
def _set_checkpt_param(cls, chkpt, prm, val, xtimish=True):
"""use config backend to store a parameter associated
with checkpoint @chkpt"""
if xtimish:
val = cls.serialize_xtime(val)
gconf.configinterface.set('checkpoint_' + prm, "%s:%s" % (escape(chkpt), val))
@staticmethod
def humantime(*tpair):
"""format xtime-like (sec, nsec) pair to human readable format"""
ts = datetime.fromtimestamp(float('.'.join(str(n) for n in tpair))).\
strftime("%Y-%m-%d %H:%M:%S")
if len(tpair) > 1:
ts += '.' + str(tpair[1])
return ts
def _crawl_time_format(self, crawl_time):
# Ex: 5 years, 4 days, 20:23:10
years, days = divmod(crawl_time.days, 365.25)
years = int(years)
days = int(days)
date=""
m, s = divmod(crawl_time.seconds, 60)
h, m = divmod(m, 60)
if years != 0:
date += "%s %s " % (years, "year" if years == 1 else "years")
if days != 0:
date += "%s %s " % (days, "day" if days == 1 else "days")
date += "%s:%s:%s" % (string.zfill(h, 2), string.zfill(m, 2), string.zfill(s, 2))
return date
def checkpt_service(self, chan, chkpt):
"""checkpoint service loop
monitor and verify checkpoint status for @chkpt, and listen
for incoming requests for whom we serve a pretty-formatted
status report"""
while True:
chkpt = gconf.configinterface.get_realtime("checkpoint")
if not chkpt:
gconf.configinterface.delete("checkpoint_completed")
gconf.configinterface.delete("checkpoint_target")
# dummy loop for the case when there is no checkpt set
select([chan], [], [])
conn, _ = chan.accept()
conn.send('\0')
conn.close()
continue
checkpt_tgt = self._checkpt_param(chkpt, 'target')
if not checkpt_tgt:
checkpt_tgt = self.xtime('.')
if isinstance(checkpt_tgt, int):
raise GsyncdError("master root directory is unaccessible (%s)",
os.strerror(checkpt_tgt))
self._set_checkpt_param(chkpt, 'target', checkpt_tgt)
logging.debug("checkpoint target %s has been determined for checkpoint %s" % \
(repr(checkpt_tgt), chkpt))
# check if the label is 'now'
chkpt_lbl = chkpt
try:
x1,x2 = chkpt.split(':')
if x1 == 'now':
chkpt_lbl = "as of " + self.humantime(x2)
except:
pass
completed = self._checkpt_param(chkpt, 'completed', xtimish=False)
if completed:
completed = tuple(int(x) for x in completed.split('.'))
s,_,_ = select([chan], [], [], (not completed) and 5 or None)
# either request made and we re-check to not
# give back stale data, or we still hunting for completion
if self.native_xtime(checkpt_tgt) and self.native_xtime(checkpt_tgt) < self.volmark:
# indexing has been reset since setting the checkpoint
status = "is invalid"
else:
xtr = self.xtime('.', self.slave)
if isinstance(xtr, int):
raise GsyncdError("slave root directory is unaccessible (%s)",
os.strerror(xtr))
ncompleted = self.xtime_geq(xtr, checkpt_tgt)
if completed and not ncompleted: # stale data
logging.warn("completion time %s for checkpoint %s became stale" % \
(self.humantime(*completed), chkpt))
completed = None
gconf.configinterface.delete('checkpoint_completed')
if ncompleted and not completed: # just reaching completion
completed = "%.6f" % time.time()
self._set_checkpt_param(chkpt, 'completed', completed, xtimish=False)
completed = tuple(int(x) for x in completed.split('.'))
logging.info("checkpoint %s completed" % chkpt)
status = completed and \
"completed at " + self.humantime(completed[0]) or \
"not reached yet"
if s:
conn = None
try:
conn, _ = chan.accept()
try:
conn.send("checkpoint %s is %s\0" % (chkpt_lbl, status))
except:
exc = sys.exc_info()[1]
if (isinstance(exc, OSError) or isinstance(exc, IOError)) and \
exc.errno == EPIPE:
logging.debug('checkpoint client disconnected')
else:
raise
finally:
if conn:
conn.close()
def start_checkpoint_thread(self):
"""prepare and start checkpoint service"""
if self.checkpoint_thread or not (
getattr(gconf, 'state_socket_unencoded', None) and getattr(gconf, 'socketdir', None)
):
return
chan = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
state_socket = os.path.join(gconf.socketdir, md5hex(gconf.state_socket_unencoded) + ".socket")
try:
os.unlink(state_socket)
except:
if sys.exc_info()[0] == OSError:
pass
chan.bind(state_socket)
chan.listen(1)
chkpt = gconf.configinterface.get_realtime("checkpoint")
t = Thread(target=self.checkpt_service, args=(chan, chkpt))
t.start()
self.checkpoint_thread = t
def add_job(self, path, label, job, *a, **kw):
"""insert @job function to job table at @path with @label"""
if self.jobtab.get(path) == None:
self.jobtab[path] = []
self.jobtab[path].append((label, a, lambda : job(*a, **kw)))
def add_failjob(self, path, label):
"""invoke .add_job with a job that does nothing just fails"""
logging.debug('salvaged: ' + label)
self.add_job(path, label, lambda: False)
def wait(self, path, *args):
"""perform jobs registered for @path
Reset jobtab entry for @path,
determine success as the conjuction of
success of all the jobs. In case of
success, call .sendmark on @path
"""
jobs = self.jobtab.pop(path, [])
succeed = True
for j in jobs:
ret = j[-1]()
if not ret:
succeed = False
if succeed and not args[0] == None:
self.sendmark(path, *args)
return succeed
def sendmark(self, path, mark, adct=None):
"""update slave side xtime for @path to master side xtime
also can send a setattr payload (see Server.setattr).
"""
if adct:
self.slave.server.setattr(path, adct)
self.set_slave_xtime(path, mark)
class GMasterChangelogMixin(GMasterCommon):
""" changelog based change detection and syncing """
# index for change type and entry
IDX_START = 0
IDX_END = 2
POS_GFID = 0
POS_TYPE = 1
POS_ENTRY1 = -1
TYPE_META = "M "
TYPE_GFID = "D "
TYPE_ENTRY = "E "
# flat directory heirarchy for gfid based access
FLAT_DIR_HIERARCHY = '.'
# maximum retries per changelog before giving up
MAX_RETRIES = 10
def fallback_xsync(self):
logging.info('falling back to xsync mode')
gconf.configinterface.set('change-detector', 'xsync')
selfkill()
def setup_working_dir(self):
workdir = os.path.join(gconf.working_dir, md5hex(gconf.local_path))
logfile = os.path.join(workdir, 'changes.log')
logging.debug('changelog working dir %s (log: %s)' % (workdir, logfile))
return (workdir, logfile)
def process_change(self, change, done, retry):
pfx = gauxpfx()
clist = []
entries = []
meta_gfid = set()
datas = set()
# basic crawl stats: files and bytes
files_pending = {'count': 0, 'purge': 0, 'bytes': 0, 'files': []}
try:
f = open(change, "r")
clist = f.readlines()
f.close()
except IOError:
raise
def edct(op, **ed):
dct = {}
dct['op'] = op
for k in ed:
if k == 'stat':
st = ed[k]
dst = dct['stat'] = {}
dst['uid'] = st.st_uid
dst['gid'] = st.st_gid
dst['mode'] = st.st_mode
else:
dct[k] = ed[k]
return dct
# entry counts (not purges)
def entry_update():
files_pending['count'] += 1
# purge count
def purge_update():
files_pending['purge'] += 1
for e in clist:
e = e.strip()
et = e[self.IDX_START:self.IDX_END] # entry type
ec = e[self.IDX_END:].split(' ') # rest of the bits
if et == self.TYPE_ENTRY:
# extract information according to the type of
# the entry operation. create(), mkdir() and mknod()
# have mode, uid, gid information in the changelog
# itself, so no need to stat()...
ty = ec[self.POS_TYPE]
# PARGFID/BNAME
en = unescape(os.path.join(pfx, ec[self.POS_ENTRY1]))
# GFID of the entry
gfid = ec[self.POS_GFID]
if ty in ['UNLINK', 'RMDIR']:
purge_update()
entries.append(edct(ty, gfid=gfid, entry=en))
elif ty in ['CREATE', 'MKDIR', 'MKNOD']:
entry_update()
# stat information present in the changelog itself
entries.append(edct(ty, gfid=gfid, entry=en, mode=int(ec[2]),\
uid=int(ec[3]), gid=int(ec[4])))
else:
# stat() to get mode and other information
go = os.path.join(pfx, gfid)
st = lstat(go)
if isinstance(st, int):
if ty == 'RENAME': # special hack for renames...
entries.append(edct('UNLINK', gfid=gfid, entry=en))
else:
logging.debug('file %s got purged in the interim' % go)
continue
if ty == 'LINK':
entry_update()
entries.append(edct(ty, stat=st, entry=en, gfid=gfid))
elif ty == 'SYMLINK':
rl = errno_wrap(os.readlink, [en], [ENOENT])
if isinstance(rl, int):
continue
entry_update()
entries.append(edct(ty, stat=st, entry=en, gfid=gfid, link=rl))
elif ty == 'RENAME':
entry_update()
e1 = unescape(os.path.join(pfx, ec[self.POS_ENTRY1 - 1]))
entries.append(edct(ty, gfid=gfid, entry=e1, entry1=en, stat=st))
else:
logging.warn('ignoring %s [op %s]' % (gfid, ty))
elif et == self.TYPE_GFID:
datas.add(os.path.join(pfx, ec[0]))
elif et == self.TYPE_META:
if ec[1] == 'SETATTR': # only setattr's for now...
meta_gfid.add(os.path.join(pfx, ec[0]))
else:
logging.warn('got invalid changelog type: %s' % (et))
logging.debug('entries: %s' % repr(entries))
if not retry:
self.update_worker_cumilitive_status(files_pending)
# sync namespace
if (entries):
self.slave.server.entry_ops(entries)
# sync metadata
if (meta_gfid):
meta_entries = []
for go in meta_gfid:
st = lstat(go)
if isinstance(st, int):
logging.debug('file %s got purged in the interim' % go)
continue
meta_entries.append(edct('META', go=go, stat=st))
if meta_entries:
self.slave.server.meta_ops(meta_entries)
# sync data
if datas:
self.a_syncdata(datas)
def process(self, changes, done=1):
tries = 0
retry = False
while True:
self.skipped_gfid_list = []
self.current_files_skipped_count = 0
# first, fire all changelog transfers in parallel. entry and metadata
# are performed synchronously, therefore in serial. However at the end
# of each changelog, data is synchronized with syncdata_async() - which
# means it is serial w.r.t entries/metadata of that changelog but
# happens in parallel with data of other changelogs.
for change in changes:
logging.debug('processing change %s' % change)
self.process_change(change, done, retry)
if not retry:
self.turns += 1 # number of changelogs processed in the batch
# Now we wait for all the data transfers fired off in the above step
# to complete. Note that this is not ideal either. Ideally we want to
# trigger the entry/meta-data transfer of the next batch while waiting
# for the data transfer of the current batch to finish.
# Note that the reason to wait for the data transfer (vs doing it
# completely in the background and call the changelog_done()
# asynchronously) is because this waiting acts as a "backpressure"
# and prevents a spiraling increase of wait stubs from consuming
# unbounded memory and resources.
# update the slave's time with the timestamp of the _last_ changelog
# file time suffix. Since, the changelog prefix time is the time when
# the changelog was rolled over, introduce a tolerence of 1 second to
# counter the small delta b/w the marker update and gettimeofday().
# NOTE: this is only for changelog mode, not xsync.
# @change is the last changelog (therefore max time for this batch)
if self.syncdata_wait():
if done:
xtl = (int(change.split('.')[-1]) - 1, 0)
self.upd_stime(xtl)
map(self.master.server.changelog_done, changes)
self.update_worker_files_syncd()
break
# We do not know which changelog transfer failed, retry everything.
retry = True
tries += 1
if tries == self.MAX_RETRIES:
logging.warn('changelogs %s could not be processed - moving on...' % \
' '.join(map(os.path.basename, changes)))
self.update_worker_total_files_skipped(self.current_files_skipped_count)
logging.warn('SKIPPED GFID = %s' % ','.join(self.skipped_gfid_list))
self.update_worker_files_syncd()
if done:
xtl = (int(change.split('.')[-1]) - 1, 0)
self.upd_stime(xtl)
map(self.master.server.changelog_done, changes)
break
# it's either entry_ops() or Rsync that failed to do it's
# job. Mostly it's entry_ops() [which currently has a problem
# of failing to create an entry but failing to return an errno]
# Therefore we do not know if it's either Rsync or the freaking
# entry_ops() that failed... so we retry the _whole_ changelog
# again.
# TODO: remove entry retries when it's gets fixed.
logging.warn('incomplete sync, retrying changelogs: %s' % \
' '.join(map(os.path.basename, changes)))
time.sleep(0.5)
def upd_stime(self, stime, path=None):
if not path:
path = self.FLAT_DIR_HIERARCHY
if not stime == URXTIME:
self.sendmark(path, stime)
def get_worker_status_file(self):
file_name = gconf.local_path+'.status'
file_name = file_name.replace("/", "_")
worker_status_file = gconf.georep_session_working_dir+file_name
return worker_status_file
def update_worker_status(self, key, value):
default_data = {"remote_node":"N/A",
"worker status":"Not Started",
"crawl status":"N/A",
"files_syncd": 0,
"files_remaining": 0,
"bytes_remaining": 0,
"purges_remaining": 0,
"total_files_skipped": 0}
worker_status_file = self.get_worker_status_file()
try:
with open(worker_status_file, 'r+') as f:
loaded_data = json.load(f)
loaded_data[key] = value
os.ftruncate(f.fileno(), 0)
os.lseek(f.fileno(), 0, os.SEEK_SET)
json.dump(loaded_data, f)
f.flush()
os.fsync(f.fileno())
except (IOError, OSError, ValueError):
logging.info ('Creating new %s' % worker_status_file)
try:
with open(worker_status_file, 'wb') as f:
default_data[key] = value
json.dump(default_data, f)
f.flush()
os.fsync(f.fileno())
except:
raise
def update_worker_cumilitive_status(self, files_pending):
default_data = {"remote_node":"N/A",
"worker status":"Not Started",
"crawl status":"N/A",
"files_syncd": 0,
"files_remaining": 0,
"bytes_remaining": 0,
"purges_remaining": 0,
"total_files_skipped": 0}
worker_status_file = self.get_worker_status_file()
try:
with open(worker_status_file, 'r+') as f:
loaded_data = json.load(f)
loaded_data['files_remaining'] = files_pending['count']
loaded_data['bytes_remaining'] = files_pending['bytes']
loaded_data['purges_remaining'] = files_pending['purge']
os.ftruncate(f.fileno(), 0)
os.lseek(f.fileno(), 0, os.SEEK_SET)
json.dump(loaded_data, f)
f.flush()
os.fsync(f.fileno())
except (IOError, OSError, ValueError):
logging.info ('Creating new %s' % worker_status_file)
try:
with open(worker_status_file, 'wb') as f:
default_data['files_remaining'] = files_pending['count']
default_data['bytes_remaining'] = files_pending['bytes']
default_data['purges_remaining'] = files_pending['purge']
json.dump(default_data, f)
f.flush()
os.fsync(f.fileno())
except:
raise
def update_worker_remote_node (self):
node = sys.argv[-1]
node = node.split("@")[-1]
remote_node_ip = node.split(":")[0]
remote_node_vol = node.split(":")[3]
remote_node = remote_node_ip + '::' + remote_node_vol
self.update_worker_status ('remote_node', remote_node)
def update_worker_health (self, state):
self.update_worker_status ('worker status', state)
def update_worker_crawl_status (self, state):
self.update_worker_status ('crawl status', state)
def update_worker_files_syncd (self):
default_data = {"remote_node":"N/A",
"worker status":"Not Started",
"crawl status":"N/A",
"files_syncd": 0,
"files_remaining": 0,
"bytes_remaining": 0,
"purges_remaining": 0,
"total_files_skipped": 0}
worker_status_file = self.get_worker_status_file()
try:
with open(worker_status_file, 'r+') as f:
loaded_data = json.load(f)
loaded_data['files_syncd'] += loaded_data['files_remaining']
loaded_data['files_remaining'] = 0
loaded_data['bytes_remaining'] = 0
loaded_data['purges_remaining'] = 0
os.ftruncate(f.fileno(), 0)
os.lseek(f.fileno(), 0, os.SEEK_SET)
json.dump(loaded_data, f)
f.flush()
os.fsync(f.fileno())
except (IOError, OSError, ValueError):
logging.info ('Creating new %s' % worker_status_file)
try:
with open(worker_status_file, 'wb') as f:
json.dump(default_data, f)
f.flush()
os.fsync(f.fileno())
except:
raise
def update_worker_files_remaining (self, state):
self.update_worker_status ('files_remaining', state)
def update_worker_bytes_remaining (self, state):
self.update_worker_status ('bytes_remaining', state)
def update_worker_purges_remaining (self, state):
self.update_worker_status ('purges_remaining', state)
def update_worker_total_files_skipped (self, value):
default_data = {"remote_node":"N/A",
"worker status":"Not Started",
"crawl status":"N/A",
"files_syncd": 0,
"files_remaining": 0,
"bytes_remaining": 0,
"purges_remaining": 0,
"total_files_skipped": 0}
worker_status_file = self.get_worker_status_file()
try:
with open(worker_status_file, 'r+') as f:
loaded_data = json.load(f)
loaded_data['total_files_skipped'] = value
loaded_data['files_remaining'] -= value
os.ftruncate(f.fileno(), 0)
os.lseek(f.fileno(), 0, os.SEEK_SET)
json.dump(loaded_data, f)
f.flush()
os.fsync(f.fileno())
except (IOError, OSError, ValueError):
logging.info ('Creating new %s' % worker_status_file)
try:
with open(worker_status_file, 'wb') as f:
default_data['total_files_skipped'] = value
json.dump(default_data, f)
f.flush()
os.fsync(f.fileno())
except:
raise
def crawl(self):
self.update_worker_crawl_status("Changelog Crawl")
changes = []
# get stime (from the brick) and purge changelogs
# that are _historical_ to that time.
purge_time = self.xtime('.', self.slave)
if isinstance(purge_time, int):
purge_time = None
try:
self.master.server.changelog_scan()
self.crawls += 1
except OSError:
self.fallback_xsync()
self.update_worker_crawl_status("Hybrid Crawl")
changes = self.master.server.changelog_getchanges()
if changes:
if purge_time:
logging.info("slave's time: %s" % repr(purge_time))
processed = [x for x in changes if int(x.split('.')[-1]) < purge_time[0]]
for pr in processed:
logging.info('skipping already processed change: %s...' % os.path.basename(pr))
self.master.server.changelog_done(pr)
changes.remove(pr)
logging.debug('processing changes %s' % repr(changes))
if changes:
self.process(changes)
def register(self):
(workdir, logfile) = self.setup_working_dir()
self.sleep_interval = int(gconf.change_interval)
# register with the changelog library
try:
# 9 == log level (DEBUG)
# 5 == connection retries
self.master.server.changelog_register(gconf.local_path,
workdir, logfile, 9, 5)
except OSError:
self.fallback_xsync()
# control should not reach here
raise
class GMasterXsyncMixin(GMasterChangelogMixin):
"""
This crawl needs to be xtime based (as of now
it's not. this is beacuse we generate CHANGELOG
file during each crawl which is then processed
by process_change()).
For now it's used as a one-shot initial sync
mechanism and only syncs directories, regular
files, hardlinks and symlinks.
"""
XSYNC_MAX_ENTRIES = 1<<13
def register(self):
self.counter = 0
self.comlist = []
self.stimes = []
self.sleep_interval = 60
self.tempdir = self.setup_working_dir()[0]
self.tempdir = os.path.join(self.tempdir, 'xsync')
logging.info('xsync temp directory: %s' % self.tempdir)
try:
os.makedirs(self.tempdir)
except OSError:
ex = sys.exc_info()[1]
if ex.errno == EEXIST and os.path.isdir(self.tempdir):
pass
else:
raise
def crawl(self):
"""
event dispatcher thread
this thread dispatches either changelog or synchronizes stime.
additionally terminates itself on recieving a 'finale' event
"""
def Xsyncer():
self.Xcrawl()
t = Thread(target=Xsyncer)
t.start()
logging.info('starting hybrid crawl...')
self.update_worker_crawl_status("Hybrid Crawl")
while True:
try:
item = self.comlist.pop(0)
if item[0] == 'finale':
logging.info('finished hybrid crawl syncing')
break
elif item[0] == 'xsync':
logging.info('processing xsync changelog %s' % (item[1]))
self.process([item[1]], 0)
elif item[0] == 'stime':
logging.debug('setting slave time: %s' % repr(item[1]))
self.upd_stime(item[1][1], item[1][0])
else:
logging.warn('unknown tuple in comlist (%s)' % repr(item))
except IndexError:
time.sleep(1)
def write_entry_change(self, prefix, data=[]):
self.fh.write("%s %s\n" % (prefix, ' '.join(data)))
def open(self):
try:
self.xsync_change = os.path.join(self.tempdir, 'XSYNC-CHANGELOG.' + str(int(time.time())))
self.fh = open(self.xsync_change, 'w')
except IOError:
raise
def close(self):
self.fh.close()
def fname(self):
return self.xsync_change
def put(self, mark, item):
self.comlist.append((mark, item))
def sync_xsync(self, last):
"""schedule a processing of changelog"""
self.close()
self.put('xsync', self.fname())
self.counter = 0
if not last:
time.sleep(1) # make sure changelogs are 1 second apart
self.open()
def sync_stime(self, stime=None, last=False):
"""schedule a stime synchronization"""
if stime:
self.put('stime', stime)
if last:
self.put('finale', None)
def sync_done(self, stime=[], last=False):
self.sync_xsync(last)
if stime:
# Send last as True only for last stime entry
for st in stime[:-1]:
self.sync_stime(st, False)
if stime and stime[-1]:
self.sync_stime(stime[-1], last)
def is_sticky(self, path, mo):
"""check for DHTs linkto sticky bit file"""
sticky = False
if mo & 01000:
sticky = self.master.server.linkto_check(path)
return sticky
def Xcrawl(self, path='.', xtr_root=None):
"""
generate a CHANGELOG file consumable by process_change.
slave's xtime (stime) is _cached_ for comparisons across
the filesystem tree, but set after directory synchronization.
"""
if path == '.':
self.open()
self.crawls += 1
if not xtr_root:
# get the root stime and use it for all comparisons
xtr_root = self.xtime('.', self.slave)
if isinstance(xtr_root, int):
if xtr_root != ENOENT:
logging.warn("slave cluster not returning the " \
"correct xtime for root (%d)" % xtr_root)
xtr_root = self.minus_infinity
xtl = self.xtime(path)
if isinstance(xtl, int):
logging.warn("master cluster's xtime not found")
xtr = self.xtime(path, self.slave)
if isinstance(xtr, int):
if xtr != ENOENT:
logging.warn("slave cluster not returning the " \
"correct xtime for %s (%d)" % (path, xtr))
xtr = self.minus_infinity
xtr = max(xtr, xtr_root)
if not self.need_sync(path, xtl, xtr):
if path == '.':
self.sync_done([(path, xtl)], True)
return
self.xtime_reversion_hook(path, xtl, xtr)
logging.debug("entering " + path)
dem = self.master.server.entries(path)
pargfid = self.master.server.gfid(path)
if isinstance(pargfid, int):
logging.warn('skipping directory %s' % (path))
for e in dem:
bname = e
e = os.path.join(path, e)
xte = self.xtime(e)
if isinstance(xte, int):
logging.warn("irregular xtime for %s: %s" % (e, errno.errorcode[xte]))
continue
if not self.need_sync(e, xte, xtr):
continue
st = self.master.server.lstat(e)
if isinstance(st, int):
logging.warn('%s got purged in the interim ...' % e)
continue
if self.is_sticky(e, st.st_mode):
logging.debug('ignoring sticky bit file %s' % e)
continue
gfid = self.master.server.gfid(e)
if isinstance(gfid, int):
logging.warn('skipping entry %s..' % e)
continue
mo = st.st_mode
self.counter += 1
if self.counter == self.XSYNC_MAX_ENTRIES:
self.sync_done(self.stimes, False)
self.stimes = []
if stat.S_ISDIR(mo):
self.write_entry_change("E", [gfid, 'MKDIR', str(mo), str(st.st_uid), str(st.st_gid), escape(os.path.join(pargfid, bname))])
self.Xcrawl(e, xtr_root)
self.stimes.append((e, xte))
elif stat.S_ISLNK(mo):
self.write_entry_change("E", [gfid, 'SYMLINK', escape(os.path.join(pargfid, bname))])
elif stat.S_ISREG(mo):
nlink = st.st_nlink
nlink -= 1 # fixup backend stat link count
# if a file has a hardlink, create a Changelog entry as 'LINK' so the slave
# side will decide if to create the new entry, or to create link.
if nlink == 1:
self.write_entry_change("E", [gfid, 'MKNOD', str(mo), str(st.st_uid), str(st.st_gid), escape(os.path.join(pargfid, bname))])
else:
self.write_entry_change("E", [gfid, 'LINK', escape(os.path.join(pargfid, bname))])
self.write_entry_change("D", [gfid])
if path == '.':
self.stimes.append((path, xtl))
self.sync_done(self.stimes, True)
class BoxClosedErr(Exception):
pass
class PostBox(list):
"""synchronized collection for storing things thought of as "requests" """
def __init__(self, *a):
list.__init__(self, *a)
# too bad Python stdlib does not have read/write locks...
# it would suffivce to grab the lock in .append as reader, in .close as writer
self.lever = Condition()
self.open = True
self.done = False
def wait(self):
"""wait on requests to be processed"""
self.lever.acquire()
if not self.done:
self.lever.wait()
self.lever.release()
return self.result
def wakeup(self, data):
"""wake up requestors with the result"""
self.result = data
self.lever.acquire()
self.done = True
self.lever.notifyAll()
self.lever.release()
def append(self, e):
"""post a request"""
self.lever.acquire()
if not self.open:
raise BoxClosedErr
list.append(self, e)
self.lever.release()
def close(self):
"""prohibit the posting of further requests"""
self.lever.acquire()
self.open = False
self.lever.release()
class Syncer(object):
"""a staged queue to relay rsync requests to rsync workers
By "staged queue" its meant that when a consumer comes to the
queue, it takes _all_ entries, leaving the queue empty.
(I don't know if there is an official term for this pattern.)
The queue uses a PostBox to accumulate incoming items.
When a consumer (rsync worker) comes, a new PostBox is
set up and the old one is passed on to the consumer.
Instead of the simplistic scheme of having one big lock
which synchronizes both the addition of new items and
PostBox exchanges, use a separate lock to arbitrate consumers,
and rely on PostBox's synchronization mechanisms take
care about additions.
There is a corner case racy situation, producers vs. consumers,
which is not handled by this scheme: namely, when the PostBox
exchange occurs in between being passed to the producer for posting
and the post placement. But that's what Postbox.close is for:
such a posting will find the PostBox closed, in which case
the producer can re-try posting against the actual PostBox of
the queue.
To aid accumlation of items in the PostBoxen before grabbed
by an rsync worker, the worker goes to sleep a bit after
each completed syncjob.
"""
def __init__(self, slave, sync_engine, resilient_errnos=[]):
"""spawn worker threads"""
self.slave = slave
self.lock = Lock()
self.pb = PostBox()
self.sync_engine = sync_engine
self.errnos_ok = resilient_errnos
for i in range(int(gconf.sync_jobs)):
t = Thread(target=self.syncjob)
t.start()
def syncjob(self):
"""the life of a worker"""
while True:
pb = None
while True:
self.lock.acquire()
if self.pb:
pb, self.pb = self.pb, PostBox()
self.lock.release()
if pb:
break
time.sleep(0.5)
pb.close()
po = self.sync_engine(pb)
if po.returncode == 0:
ret = (True, 0)
elif po.returncode in self.errnos_ok:
ret = (False, po.returncode)
else:
po.errfail()
pb.wakeup(ret)
def add(self, e):
while True:
pb = self.pb
try:
pb.append(e)
return pb
except BoxClosedErr:
pass
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