204
216
:return: The root chk of the resulting CHKMap.
206
result = CHKMap(store, None, search_key_func=search_key_func)
218
root_key = klass._create_directly(store, initial_value,
219
maximum_size=maximum_size, key_width=key_width,
220
search_key_func=search_key_func)
224
def _create_via_map(klass, store, initial_value, maximum_size=0,
225
key_width=1, search_key_func=None):
226
result = klass(store, None, search_key_func=search_key_func)
207
227
result._root_node.set_maximum_size(maximum_size)
208
228
result._root_node._key_width = key_width
210
230
for key, value in initial_value.items():
211
231
delta.append((None, key, value))
212
return result.apply_delta(delta)
232
root_key = result.apply_delta(delta)
236
def _create_directly(klass, store, initial_value, maximum_size=0,
237
key_width=1, search_key_func=None):
238
node = LeafNode(search_key_func=search_key_func)
239
node.set_maximum_size(maximum_size)
240
node._key_width = key_width
241
node._items = dict(initial_value)
242
node._raw_size = sum([node._key_value_len(key, value)
243
for key,value in initial_value.iteritems()])
244
node._len = len(node._items)
245
node._compute_search_prefix()
246
node._compute_serialised_prefix()
249
and node._current_size() > maximum_size):
250
prefix, node_details = node._split(store)
251
if len(node_details) == 1:
252
raise AssertionError('Failed to split using node._split')
253
node = InternalNode(prefix, search_key_func=search_key_func)
254
node.set_maximum_size(maximum_size)
255
node._key_width = key_width
256
for split, subnode in node_details:
257
node.add_node(split, subnode)
258
keys = list(node.serialise(store))
214
261
def iter_changes(self, basis):
215
262
"""Iterate over the changes between basis and self.
1354
def _find_children_info(store, interesting_keys, uninteresting_keys, pb):
1355
"""Read the associated records, and determine what is interesting."""
1356
uninteresting_keys = set(uninteresting_keys)
1357
chks_to_read = uninteresting_keys.union(interesting_keys)
1358
next_uninteresting = set()
1359
next_interesting = set()
1360
uninteresting_items = set()
1361
interesting_items = set()
1362
interesting_to_yield = []
1363
for record in store.get_record_stream(chks_to_read, 'unordered', True):
1364
# records_read.add(record.key())
1367
bytes = record.get_bytes_as('fulltext')
1368
# We don't care about search_key_func for this code, because we only
1369
# care about external references.
1370
node = _deserialise(bytes, record.key, search_key_func=None)
1371
if record.key in uninteresting_keys:
1372
if type(node) is InternalNode:
1373
next_uninteresting.update(node.refs())
1375
# We know we are at a LeafNode, so we can pass None for the
1377
uninteresting_items.update(node.iteritems(None))
1379
interesting_to_yield.append(record.key)
1380
if type(node) is InternalNode:
1381
next_interesting.update(node.refs())
1383
interesting_items.update(node.iteritems(None))
1384
return (next_uninteresting, uninteresting_items,
1385
next_interesting, interesting_to_yield, interesting_items)
1388
def _find_all_uninteresting(store, interesting_root_keys,
1389
uninteresting_root_keys, pb):
1390
"""Determine the full set of uninteresting keys."""
1391
# What about duplicates between interesting_root_keys and
1392
# uninteresting_root_keys?
1393
if not uninteresting_root_keys:
1394
# Shortcut case. We know there is nothing uninteresting to filter out
1395
# So we just let the rest of the algorithm do the work
1396
# We know there is nothing uninteresting, and we didn't have to read
1397
# any interesting records yet.
1398
return (set(), set(), set(interesting_root_keys), [], set())
1399
all_uninteresting_chks = set(uninteresting_root_keys)
1400
all_uninteresting_items = set()
1402
# First step, find the direct children of both the interesting and
1404
(uninteresting_keys, uninteresting_items,
1405
interesting_keys, interesting_to_yield,
1406
interesting_items) = _find_children_info(store, interesting_root_keys,
1407
uninteresting_root_keys,
1409
all_uninteresting_chks.update(uninteresting_keys)
1410
all_uninteresting_items.update(uninteresting_items)
1411
del uninteresting_items
1412
# Note: Exact matches between interesting and uninteresting do not need
1413
# to be search further. Non-exact matches need to be searched in case
1414
# there is a future exact-match
1415
uninteresting_keys.difference_update(interesting_keys)
1417
# Second, find the full set of uninteresting bits reachable by the
1418
# uninteresting roots
1419
chks_to_read = uninteresting_keys
1422
for record in store.get_record_stream(chks_to_read, 'unordered', False):
1423
# TODO: Handle 'absent'
1417
class CHKMapDifference(object):
1418
"""Iterate the stored pages and key,value pairs for (new - old).
1420
This class provides a generator over the stored CHK pages and the
1421
(key, value) pairs that are in any of the new maps and not in any of the
1424
Note that it may yield chk pages that are common (especially root nodes),
1425
but it won't yield (key,value) pairs that are common.
1428
def __init__(self, store, new_root_keys, old_root_keys,
1429
search_key_func, pb=None):
1431
self._new_root_keys = new_root_keys
1432
self._old_root_keys = old_root_keys
1434
# All uninteresting chks that we have seen. By the time they are added
1435
# here, they should be either fully ignored, or queued up for
1437
self._all_old_chks = set(self._old_root_keys)
1438
# All items that we have seen from the old_root_keys
1439
self._all_old_items = set()
1440
# These are interesting items which were either read, or already in the
1441
# interesting queue (so we don't need to walk them again)
1442
self._processed_new_refs = set()
1443
self._search_key_func = search_key_func
1445
# The uninteresting and interesting nodes to be searched
1446
self._old_queue = []
1447
self._new_queue = []
1448
# Holds the (key, value) items found when processing the root nodes,
1449
# waiting for the uninteresting nodes to be walked
1450
self._new_item_queue = []
1453
def _read_nodes_from_store(self, keys):
1454
# We chose not to use _page_cache, because we think in terms of records
1455
# to be yielded. Also, we expect to touch each page only 1 time during
1456
# this code. (We may want to evaluate saving the raw bytes into the
1457
# page cache, which would allow a working tree update after the fetch
1458
# to not have to read the bytes again.)
1459
stream = self._store.get_record_stream(keys, 'unordered', True)
1460
for record in stream:
1461
if self._pb is not None:
1463
if record.storage_kind == 'absent':
1464
raise errors.NoSuchRevision(self._store, record.key)
1426
1465
bytes = record.get_bytes_as('fulltext')
1427
# We don't care about search_key_func for this code, because we
1428
# only care about external references.
1429
node = _deserialise(bytes, record.key, search_key_func=None)
1466
node = _deserialise(bytes, record.key,
1467
search_key_func=self._search_key_func)
1430
1468
if type(node) is InternalNode:
1431
# uninteresting_prefix_chks.update(node._items.iteritems())
1432
chks = node._items.values()
1433
# TODO: We remove the entries that are already in
1434
# uninteresting_chks ?
1435
next_chks.update(chks)
1436
all_uninteresting_chks.update(chks)
1469
# Note we don't have to do node.refs() because we know that
1470
# there are no children that have been pushed into this node
1471
prefix_refs = node._items.items()
1438
all_uninteresting_items.update(node._items.iteritems())
1439
chks_to_read = next_chks
1440
return (all_uninteresting_chks, all_uninteresting_items,
1441
interesting_keys, interesting_to_yield, interesting_items)
1475
items = node._items.items()
1476
yield record, node, prefix_refs, items
1478
def _read_old_roots(self):
1479
old_chks_to_enqueue = []
1480
all_old_chks = self._all_old_chks
1481
for record, node, prefix_refs, items in \
1482
self._read_nodes_from_store(self._old_root_keys):
1483
# Uninteresting node
1484
prefix_refs = [p_r for p_r in prefix_refs
1485
if p_r[1] not in all_old_chks]
1486
new_refs = [p_r[1] for p_r in prefix_refs]
1487
all_old_chks.update(new_refs)
1488
self._all_old_items.update(items)
1489
# Queue up the uninteresting references
1490
# Don't actually put them in the 'to-read' queue until we have
1491
# finished checking the interesting references
1492
old_chks_to_enqueue.extend(prefix_refs)
1493
return old_chks_to_enqueue
1495
def _enqueue_old(self, new_prefixes, old_chks_to_enqueue):
1496
# At this point, we have read all the uninteresting and interesting
1497
# items, so we can queue up the uninteresting stuff, knowing that we've
1498
# handled the interesting ones
1499
for prefix, ref in old_chks_to_enqueue:
1500
not_interesting = True
1501
for i in xrange(len(prefix), 0, -1):
1502
if prefix[:i] in new_prefixes:
1503
not_interesting = False
1506
# This prefix is not part of the remaining 'interesting set'
1508
self._old_queue.append(ref)
1510
def _read_all_roots(self):
1511
"""Read the root pages.
1513
This is structured as a generator, so that the root records can be
1514
yielded up to whoever needs them without any buffering.
1516
# This is the bootstrap phase
1517
if not self._old_root_keys:
1518
# With no old_root_keys we can just shortcut and be ready
1519
# for _flush_new_queue
1520
self._new_queue = list(self._new_root_keys)
1522
old_chks_to_enqueue = self._read_old_roots()
1523
# filter out any root keys that are already known to be uninteresting
1524
new_keys = set(self._new_root_keys).difference(self._all_old_chks)
1525
# These are prefixes that are present in new_keys that we are
1527
new_prefixes = set()
1528
# We are about to yield all of these, so we don't want them getting
1529
# added a second time
1530
processed_new_refs = self._processed_new_refs
1531
processed_new_refs.update(new_keys)
1532
for record, node, prefix_refs, items in \
1533
self._read_nodes_from_store(new_keys):
1534
# At this level, we now know all the uninteresting references
1535
# So we filter and queue up whatever is remaining
1536
prefix_refs = [p_r for p_r in prefix_refs
1537
if p_r[1] not in self._all_old_chks
1538
and p_r[1] not in processed_new_refs]
1539
refs = [p_r[1] for p_r in prefix_refs]
1540
new_prefixes.update([p_r[0] for p_r in prefix_refs])
1541
self._new_queue.extend(refs)
1542
# TODO: We can potentially get multiple items here, however the
1543
# current design allows for this, as callers will do the work
1544
# to make the results unique. We might profile whether we
1545
# gain anything by ensuring unique return values for items
1546
new_items = [item for item in items
1547
if item not in self._all_old_items]
1548
self._new_item_queue.extend(new_items)
1549
new_prefixes.update([self._search_key_func(item[0])
1550
for item in new_items])
1551
processed_new_refs.update(refs)
1553
# For new_prefixes we have the full length prefixes queued up.
1554
# However, we also need possible prefixes. (If we have a known ref to
1555
# 'ab', then we also need to include 'a'.) So expand the
1556
# new_prefixes to include all shorter prefixes
1557
for prefix in list(new_prefixes):
1558
new_prefixes.update([prefix[:i] for i in xrange(1, len(prefix))])
1559
self._enqueue_old(new_prefixes, old_chks_to_enqueue)
1561
def _flush_new_queue(self):
1562
# No need to maintain the heap invariant anymore, just pull things out
1564
refs = set(self._new_queue)
1565
self._new_queue = []
1566
# First pass, flush all interesting items and convert to using direct refs
1567
all_old_chks = self._all_old_chks
1568
processed_new_refs = self._processed_new_refs
1569
all_old_items = self._all_old_items
1570
new_items = [item for item in self._new_item_queue
1571
if item not in all_old_items]
1572
self._new_item_queue = []
1574
yield None, new_items
1575
refs = refs.difference(all_old_chks)
1578
next_refs_update = next_refs.update
1579
# Inlining _read_nodes_from_store improves 'bzr branch bzr.dev'
1580
# from 1m54s to 1m51s. Consider it.
1581
for record, _, p_refs, items in self._read_nodes_from_store(refs):
1582
items = [item for item in items
1583
if item not in all_old_items]
1585
next_refs_update([p_r[1] for p_r in p_refs])
1586
next_refs = next_refs.difference(all_old_chks)
1587
next_refs = next_refs.difference(processed_new_refs)
1588
processed_new_refs.update(next_refs)
1591
def _process_next_old(self):
1592
# Since we don't filter uninteresting any further than during
1593
# _read_all_roots, process the whole queue in a single pass.
1594
refs = self._old_queue
1595
self._old_queue = []
1596
all_old_chks = self._all_old_chks
1597
for record, _, prefix_refs, items in self._read_nodes_from_store(refs):
1598
self._all_old_items.update(items)
1599
refs = [r for _,r in prefix_refs if r not in all_old_chks]
1600
self._old_queue.extend(refs)
1601
all_old_chks.update(refs)
1603
def _process_queues(self):
1604
while self._old_queue:
1605
self._process_next_old()
1606
return self._flush_new_queue()
1609
for record in self._read_all_roots():
1611
for record, items in self._process_queues():
1444
1615
def iter_interesting_nodes(store, interesting_root_keys,
1456
1627
(interesting record, {interesting key:values})
1458
# TODO: consider that it may be more memory efficient to use the 20-byte
1459
# sha1 string, rather than tuples of hexidecimal sha1 strings.
1460
# TODO: Try to factor out a lot of the get_record_stream() calls into a
1461
# helper function similar to _read_bytes. This function should be
1462
# able to use nodes from the _page_cache as well as actually
1463
# requesting bytes from the store.
1465
(all_uninteresting_chks, all_uninteresting_items, interesting_keys,
1466
interesting_to_yield, interesting_items) = _find_all_uninteresting(store,
1467
interesting_root_keys, uninteresting_root_keys, pb)
1469
# Now that we know everything uninteresting, we can yield information from
1471
interesting_items.difference_update(all_uninteresting_items)
1472
interesting_to_yield = set(interesting_to_yield) - all_uninteresting_chks
1473
if interesting_items:
1474
yield None, interesting_items
1475
if interesting_to_yield:
1476
# We request these records again, rather than buffering the root
1477
# records, most likely they are still in the _group_cache anyway.
1478
for record in store.get_record_stream(interesting_to_yield,
1479
'unordered', False):
1481
all_uninteresting_chks.update(interesting_to_yield)
1482
interesting_keys.difference_update(all_uninteresting_chks)
1484
chks_to_read = interesting_keys
1488
for record in store.get_record_stream(chks_to_read, 'unordered', False):
1491
pb.update('find chk pages', counter)
1492
# TODO: Handle 'absent'?
1493
bytes = record.get_bytes_as('fulltext')
1494
# We don't care about search_key_func for this code, because we
1495
# only care about external references.
1496
node = _deserialise(bytes, record.key, search_key_func=None)
1497
if type(node) is InternalNode:
1498
# all_uninteresting_chks grows large, as it lists all nodes we
1499
# don't want to process (including already seen interesting
1501
# small.difference_update(large) scales O(large), but
1502
# small.difference(large) scales O(small).
1503
# Also, we know we just _deserialised this node, so we can
1504
# access the dict directly.
1505
chks = set(node._items.itervalues()).difference(
1506
all_uninteresting_chks)
1507
# Is set() and .difference_update better than:
1508
# chks = [chk for chk in node.refs()
1509
# if chk not in all_uninteresting_chks]
1510
next_chks.update(chks)
1511
# These are now uninteresting everywhere else
1512
all_uninteresting_chks.update(chks)
1513
interesting_items = []
1515
interesting_items = [item for item in node._items.iteritems()
1516
if item not in all_uninteresting_items]
1517
# TODO: Do we need to filter out items that we have already
1518
# seen on other pages? We don't really want to buffer the
1519
# whole thing, but it does mean that callers need to
1520
# understand they may get duplicate values.
1521
# all_uninteresting_items.update(interesting_items)
1522
yield record, interesting_items
1523
chks_to_read = next_chks
1629
iterator = CHKMapDifference(store, interesting_root_keys,
1630
uninteresting_root_keys,
1631
search_key_func=store._search_key_func,
1633
return iterator.process()
added
removed
bzrlib/chk_map.py
