src/allmydata/test/test_hung_server.py

   1 # -*- coding: utf-8 -*-
   2
   3 import os, shutil
   4 from twisted.trial import unittest
   5 from twisted.internet import defer
   6 from allmydata import uri
   7 from allmydata.util.consumer import download_to_data
   8 from allmydata.immutable import upload
   9 from allmydata.mutable.common import UnrecoverableFileError
  10 from allmydata.storage.common import storage_index_to_dir
  11 from allmydata.test.no_network import GridTestMixin
  12 from allmydata.test.common import ShouldFailMixin
  13 from allmydata.util.pollmixin import PollMixin
  14 from allmydata.interfaces import NotEnoughSharesError
  15
  16 immutable_plaintext = "data" * 10000
  17 mutable_plaintext = "muta" * 10000
  18
  19 class HungServerDownloadTest(GridTestMixin, ShouldFailMixin, PollMixin,
  20                              unittest.TestCase):
  21     # Many of these tests take around 60 seconds on François's ARM buildslave:
  22     # http://tahoe-lafs.org/buildbot/builders/FranXois%20lenny-armv5tel
  23     # allmydata.test.test_hung_server.HungServerDownloadTest.test_2_good_8_broken_duplicate_share_fail
  24     # once ERRORed after 197 seconds on Midnight Magic's NetBSD buildslave:
  25     # http://tahoe-lafs.org/buildbot/builders/MM%20netbsd4%20i386%20warp
  26     # MM's buildslave varies a lot in how long it takes to run tests.
  27
  28     timeout = 240
  29
  30     def _break(self, servers):
  31         for (id, ss) in servers:
  32             self.g.break_server(id)
  33
  34     def _hang(self, servers, **kwargs):
  35         for (id, ss) in servers:
  36             self.g.hang_server(id, **kwargs)
  37
  38     def _unhang(self, servers, **kwargs):
  39         for (id, ss) in servers:
  40             self.g.unhang_server(id, **kwargs)
  41
  42     def _hang_shares(self, shnums, **kwargs):
  43         # hang all servers who are holding the given shares
  44         hung_serverids = set()
  45         for (i_shnum, i_serverid, i_sharefile) in self.shares:
  46             if i_shnum in shnums:
  47                 if i_serverid not in hung_serverids:
  48                     self.g.hang_server(i_serverid, **kwargs)
  49                     hung_serverids.add(i_serverid)
  50
  51     def _delete_all_shares_from(self, servers):
  52         serverids = [id for (id, ss) in servers]
  53         for (i_shnum, i_serverid, i_sharefile) in self.shares:
  54             if i_serverid in serverids:
  55                 os.unlink(i_sharefile)
  56
  57     def _corrupt_all_shares_in(self, servers, corruptor_func):
  58         serverids = [id for (id, ss) in servers]
  59         for (i_shnum, i_serverid, i_sharefile) in self.shares:
  60             if i_serverid in serverids:
  61                 self._corrupt_share((i_shnum, i_sharefile), corruptor_func)
  62
  63     def _copy_all_shares_from(self, from_servers, to_server):
  64         serverids = [id for (id, ss) in from_servers]
  65         for (i_shnum, i_serverid, i_sharefile) in self.shares:
  66             if i_serverid in serverids:
  67                 self._copy_share((i_shnum, i_sharefile), to_server)
  68
  69     def _copy_share(self, share, to_server):
  70         (sharenum, sharefile) = share
  71         (id, ss) = to_server
  72         shares_dir = os.path.join(ss.original.storedir, "shares")
  73         si = uri.from_string(self.uri).get_storage_index()
  74         si_dir = os.path.join(shares_dir, storage_index_to_dir(si))
  75         if not os.path.exists(si_dir):
  76             os.makedirs(si_dir)
  77         new_sharefile = os.path.join(si_dir, str(sharenum))
  78         shutil.copy(sharefile, new_sharefile)
  79         self.shares = self.find_uri_shares(self.uri)
  80         # Make sure that the storage server has the share.
  81         self.failUnless((sharenum, ss.original.my_nodeid, new_sharefile)
  82                         in self.shares)
  83
  84     def _corrupt_share(self, share, corruptor_func):
  85         (sharenum, sharefile) = share
  86         data = open(sharefile, "rb").read()
  87         newdata = corruptor_func(data)
  88         os.unlink(sharefile)
  89         wf = open(sharefile, "wb")
  90         wf.write(newdata)
  91         wf.close()
  92
  93     def _set_up(self, mutable, testdir, num_clients=1, num_servers=10):
  94         self.mutable = mutable
  95         if mutable:
  96             self.basedir = "hung_server/mutable_" + testdir
  97         else:
  98             self.basedir = "hung_server/immutable_" + testdir
  99
 100         self.set_up_grid(num_clients=num_clients, num_servers=num_servers)
 101
 102         self.c0 = self.g.clients[0]
 103         nm = self.c0.nodemaker
 104         self.servers = sorted([(s.get_serverid(), s.get_rref())
 105                                for s in nm.storage_broker.get_connected_servers()])
 106         self.servers = self.servers[5:] + self.servers[:5]
 107
 108         if mutable:
 109             d = nm.create_mutable_file(mutable_plaintext)
 110             def _uploaded_mutable(node):
 111                 self.uri = node.get_uri()
 112                 self.shares = self.find_uri_shares(self.uri)
 113             d.addCallback(_uploaded_mutable)
 114         else:
 115             data = upload.Data(immutable_plaintext, convergence="")
 116             d = self.c0.upload(data)
 117             def _uploaded_immutable(upload_res):
 118                 self.uri = upload_res.uri
 119                 self.shares = self.find_uri_shares(self.uri)
 120             d.addCallback(_uploaded_immutable)
 121         return d
 122
 123     def _start_download(self):
 124         n = self.c0.create_node_from_uri(self.uri)
 125         if self.mutable:
 126             d = n.download_best_version()
 127         else:
 128             d = download_to_data(n)
 129         return d
 130
 131     def _wait_for_data(self, n):
 132         if self.mutable:
 133             d = n.download_best_version()
 134         else:
 135             d = download_to_data(n)
 136         return d
 137
 138     def _check(self, resultingdata):
 139         if self.mutable:
 140             self.failUnlessEqual(resultingdata, mutable_plaintext)
 141         else:
 142             self.failUnlessEqual(resultingdata, immutable_plaintext)
 143
 144     def _download_and_check(self):
 145         d = self._start_download()
 146         d.addCallback(self._check)
 147         return d
 148
 149     def _should_fail_download(self):
 150         if self.mutable:
 151             return self.shouldFail(UnrecoverableFileError, self.basedir,
 152                                    "no recoverable versions",
 153                                    self._download_and_check)
 154         else:
 155             return self.shouldFail(NotEnoughSharesError, self.basedir,
 156                                    "ran out of shares",
 157                                    self._download_and_check)
 158
 159
 160     def test_10_good_sanity_check(self):
 161         d = defer.succeed(None)
 162         for mutable in [False, True]:
 163             d.addCallback(lambda ign: self._set_up(mutable, "test_10_good_sanity_check"))
 164             d.addCallback(lambda ign: self._download_and_check())
 165         return d
 166
 167     def test_10_good_copied_share(self):
 168         d = defer.succeed(None)
 169         for mutable in [False, True]:
 170             d.addCallback(lambda ign: self._set_up(mutable, "test_10_good_copied_share"))
 171             d.addCallback(lambda ign: self._copy_all_shares_from(self.servers[2:3], self.servers[0]))
 172             d.addCallback(lambda ign: self._download_and_check())
 173             return d
 174
 175     def test_3_good_7_noshares(self):
 176         d = defer.succeed(None)
 177         for mutable in [False, True]:
 178             d.addCallback(lambda ign: self._set_up(mutable, "test_3_good_7_noshares"))
 179             d.addCallback(lambda ign: self._delete_all_shares_from(self.servers[3:]))
 180             d.addCallback(lambda ign: self._download_and_check())
 181         return d
 182
 183     def test_2_good_8_broken_fail(self):
 184         d = defer.succeed(None)
 185         for mutable in [False, True]:
 186             d.addCallback(lambda ign: self._set_up(mutable, "test_2_good_8_broken_fail"))
 187             d.addCallback(lambda ign: self._break(self.servers[2:]))
 188             d.addCallback(lambda ign: self._should_fail_download())
 189         return d
 190
 191     def test_2_good_8_noshares_fail(self):
 192         d = defer.succeed(None)
 193         for mutable in [False, True]:
 194             d.addCallback(lambda ign: self._set_up(mutable, "test_2_good_8_noshares_fail"))
 195             d.addCallback(lambda ign: self._delete_all_shares_from(self.servers[2:]))
 196             d.addCallback(lambda ign: self._should_fail_download())
 197         return d
 198
 199     def test_2_good_8_broken_copied_share(self):
 200         d = defer.succeed(None)
 201         for mutable in [False, True]:
 202             d.addCallback(lambda ign: self._set_up(mutable, "test_2_good_8_broken_copied_share"))
 203             d.addCallback(lambda ign: self._copy_all_shares_from(self.servers[2:3], self.servers[0]))
 204             d.addCallback(lambda ign: self._break(self.servers[2:]))
 205             d.addCallback(lambda ign: self._download_and_check())
 206         return d
 207
 208     def test_2_good_8_broken_duplicate_share_fail(self):
 209         d = defer.succeed(None)
 210         for mutable in [False, True]:
 211             d.addCallback(lambda ign: self._set_up(mutable, "test_2_good_8_broken_duplicate_share_fail"))
 212             d.addCallback(lambda ign: self._copy_all_shares_from(self.servers[1:2], self.servers[0]))
 213             d.addCallback(lambda ign: self._break(self.servers[2:]))
 214             d.addCallback(lambda ign: self._should_fail_download())
 215         return d
 216
 217     def test_3_good_7_hung_immutable(self):
 218         d = defer.succeed(None)
 219         d.addCallback(lambda ign: self._set_up(False, "test_3_good_7_hung"))
 220         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 221         d.addCallback(lambda ign: self._download_and_check())
 222         return d
 223
 224     def test_5_overdue_immutable(self):
 225         # restrict the ShareFinder to only allow 5 outstanding requests, and
 226         # arrange for the first 5 servers to hang. Then trigger the OVERDUE
 227         # timers (simulating 10 seconds passed), at which point the
 228         # ShareFinder should send additional queries and finish the download
 229         # quickly. If we didn't have OVERDUE timers, this test would fail by
 230         # timing out.
 231         done = []
 232         d = self._set_up(False, "test_5_overdue_immutable")
 233         def _reduce_max_outstanding_requests_and_download(ign):
 234             self._hang_shares(range(5))
 235             n = self.c0.create_node_from_uri(self.uri)
 236             n._cnode._maybe_create_download_node()
 237             self._sf = n._cnode._node._sharefinder
 238             self._sf.max_outstanding_requests = 5
 239             self._sf.OVERDUE_TIMEOUT = 1000.0
 240             d2 = download_to_data(n)
 241             # start download, but don't wait for it to complete yet
 242             def _done(res):
 243                 done.append(res) # we will poll for this later
 244             d2.addBoth(_done)
 245         d.addCallback(_reduce_max_outstanding_requests_and_download)
 246         from foolscap.eventual import fireEventually, flushEventualQueue
 247         # wait here a while
 248         d.addCallback(lambda res: fireEventually(res))
 249         d.addCallback(lambda res: flushEventualQueue())
 250         d.addCallback(lambda ign: self.failIf(done))
 251         def _check_waiting(ign):
 252             # all the share requests should now be stuck waiting
 253             self.failUnlessEqual(len(self._sf.pending_requests), 5)
 254             # but none should be marked as OVERDUE until the timers expire
 255             self.failUnlessEqual(len(self._sf.overdue_requests), 0)
 256         d.addCallback(_check_waiting)
 257         def _mark_overdue(ign):
 258             # declare four requests overdue, allowing new requests to take
 259             # their place, and leaving one stuck. The finder will keep
 260             # sending requests until there are 5 non-overdue ones
 261             # outstanding, at which point we'll have 4 OVERDUE, 1
 262             # stuck-but-not-overdue, and 4 live requests. All 4 live requests
 263             # will retire before the download is complete and the ShareFinder
 264             # is shut off. That will leave 4 OVERDUE and 1
 265             # stuck-but-not-overdue, for a total of 5 requests in in
 266             # _sf.pending_requests
 267             for t in self._sf.overdue_timers.values()[:4]:
 268                 t.reset(-1.0)
 269             # the timers ought to fire before the eventual-send does
 270             return fireEventually()
 271         d.addCallback(_mark_overdue)
 272         def _we_are_done():
 273             return bool(done)
 274         d.addCallback(lambda ign: self.poll(_we_are_done))
 275         def _check_done(ign):
 276             self.failUnlessEqual(done, [immutable_plaintext])
 277             self.failUnlessEqual(len(self._sf.pending_requests), 5)
 278             self.failUnlessEqual(len(self._sf.overdue_requests), 4)
 279         d.addCallback(_check_done)
 280         return d
 281
 282     def test_2_good_8_hung_then_1_recovers_immutable(self):
 283         d = defer.succeed(None)
 284         d.addCallback(lambda ign: self._set_up(False, "test_2_good_8_hung_then_1_recovers"))
 285         d.addCallback(lambda ign: self._hang(self.servers[2:3]))
 286         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 287         d.addCallback(lambda ign: self._unhang(self.servers[2:3]))
 288         d.addCallback(lambda ign: self._download_and_check())
 289         return d
 290
 291     def test_2_good_8_hung_then_1_recovers_with_2_shares_immutable(self):
 292         d = defer.succeed(None)
 293         d.addCallback(lambda ign: self._set_up(False, "test_2_good_8_hung_then_1_recovers_with_2_shares"))
 294         d.addCallback(lambda ign: self._copy_all_shares_from(self.servers[0:1], self.servers[2]))
 295         d.addCallback(lambda ign: self._hang(self.servers[2:3]))
 296         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 297         d.addCallback(lambda ign: self._unhang(self.servers[2:3]))
 298         d.addCallback(lambda ign: self._download_and_check())
 299         return d
 300
 301     # The tests below do not currently pass for mutable files. The
 302     # mutable-file downloader does not yet handle hung servers, and the tests
 303     # hang forever (hence the use of SkipTest rather than .todo)
 304
 305     def test_3_good_7_hung_mutable(self):
 306         raise unittest.SkipTest("still broken")
 307         d = defer.succeed(None)
 308         d.addCallback(lambda ign: self._set_up(True, "test_3_good_7_hung"))
 309         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 310         d.addCallback(lambda ign: self._download_and_check())
 311         return d
 312
 313     def test_2_good_8_hung_then_1_recovers_mutable(self):
 314         raise unittest.SkipTest("still broken")
 315         d = defer.succeed(None)
 316         d.addCallback(lambda ign: self._set_up(True, "test_2_good_8_hung_then_1_recovers"))
 317         d.addCallback(lambda ign: self._hang(self.servers[2:3]))
 318         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 319         d.addCallback(lambda ign: self._unhang(self.servers[2:3]))
 320         d.addCallback(lambda ign: self._download_and_check())
 321         return d
 322
 323     def test_2_good_8_hung_then_1_recovers_with_2_shares_mutable(self):
 324         raise unittest.SkipTest("still broken")
 325         d = defer.succeed(None)
 326         d.addCallback(lambda ign: self._set_up(True, "test_2_good_8_hung_then_1_recovers_with_2_shares"))
 327         d.addCallback(lambda ign: self._copy_all_shares_from(self.servers[0:1], self.servers[2]))
 328         d.addCallback(lambda ign: self._hang(self.servers[2:3]))
 329         d.addCallback(lambda ign: self._hang(self.servers[3:]))
 330         d.addCallback(lambda ign: self._unhang(self.servers[2:3]))
 331         d.addCallback(lambda ign: self._download_and_check())
 332         return d