]> git.openstreetmap.org Git - nominatim.git/commitdiff
factor out async connection handling into separate class
authorSarah Hoffmann <lonvia@denofr.de>
Tue, 20 Apr 2021 09:16:12 +0000 (11:16 +0200)
committerSarah Hoffmann <lonvia@denofr.de>
Tue, 20 Apr 2021 12:08:37 +0000 (14:08 +0200)
Also adds a test for reconnecting regularly while indexing.

nominatim/indexer/indexer.py
test/python/test_indexing.py

index aa1fb8efb80c4c6156f0547e1fa71c1e76cc72d4..a064b28580168cca6cb26a32bc1e398ea3f43442 100644 (file)
@@ -11,25 +11,76 @@ from nominatim.db.connection import connect
 
 LOG = logging.getLogger()
 
+class WorkerPool:
+    """ A pool of asynchronous database connections.
 
-class Indexer:
-    """ Main indexing routine.
+        The pool may be used as a context manager.
     """
+    REOPEN_CONNECTIONS_AFTER = 100000
 
-    def __init__(self, dsn, num_threads):
-        self.dsn = dsn
-        self.num_threads = num_threads
-        self.threads = []
+    def __init__(self, dsn, pool_size):
+        self.threads = [DBConnection(dsn) for _ in range(pool_size)]
+        self.free_workers = self._yield_free_worker()
 
 
-    def _setup_connections(self):
-        self.threads = [DBConnection(self.dsn) for _ in range(self.num_threads)]
+    def finish_all(self):
+        """ Wait for all connection to finish.
+        """
+        for thread in self.threads:
+            while not thread.is_done():
+                thread.wait()
 
+        self.free_workers = self._yield_free_worker()
 
-    def _close_connections(self):
+    def close(self):
+        """ Close all connections and clear the pool.
+        """
         for thread in self.threads:
             thread.close()
         self.threads = []
+        self.free_workers = None
+
+
+    def next_free_worker(self):
+        """ Get the next free connection.
+        """
+        return next(self.free_workers)
+
+
+    def _yield_free_worker(self):
+        ready = self.threads
+        command_stat = 0
+        while True:
+            for thread in ready:
+                if thread.is_done():
+                    command_stat += 1
+                    yield thread
+
+            if command_stat > self.REOPEN_CONNECTIONS_AFTER:
+                for thread in self.threads:
+                    while not thread.is_done():
+                        thread.wait()
+                    thread.connect()
+                ready = self.threads
+            else:
+                _, ready, _ = select.select([], self.threads, [])
+
+
+    def __enter__(self):
+        return self
+
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        self.close()
+
+
+class Indexer:
+    """ Main indexing routine.
+    """
+
+    def __init__(self, dsn, num_threads):
+        self.dsn = dsn
+        self.num_threads = num_threads
 
 
     def index_full(self, analyse=True):
@@ -42,27 +93,27 @@ class Indexer:
             conn.autocommit = True
 
             if analyse:
-                def _analyse():
+                def _analyze():
                     with conn.cursor() as cur:
-                        cur.execute('ANALYSE')
+                        cur.execute('ANALYZE')
             else:
-                def _analyse():
+                def _analyze():
                     pass
 
             self.index_by_rank(0, 4)
-            _analyse()
+            _analyze()
 
             self.index_boundaries(0, 30)
-            _analyse()
+            _analyze()
 
             self.index_by_rank(5, 25)
-            _analyse()
+            _analyze()
 
             self.index_by_rank(26, 30)
-            _analyse()
+            _analyze()
 
             self.index_postcodes()
-            _analyse()
+            _analyze()
 
 
     def index_boundaries(self, minrank, maxrank):
@@ -71,13 +122,8 @@ class Indexer:
         LOG.warning("Starting indexing boundaries using %s threads",
                     self.num_threads)
 
-        self._setup_connections()
-
-        try:
-            for rank in range(max(minrank, 4), min(maxrank, 26)):
-                self._index(runners.BoundaryRunner(rank))
-        finally:
-            self._close_connections()
+        for rank in range(max(minrank, 4), min(maxrank, 26)):
+            self._index(runners.BoundaryRunner(rank))
 
     def index_by_rank(self, minrank, maxrank):
         """ Index all entries of placex in the given rank range (inclusive)
@@ -90,20 +136,15 @@ class Indexer:
         LOG.warning("Starting indexing rank (%i to %i) using %i threads",
                     minrank, maxrank, self.num_threads)
 
-        self._setup_connections()
+        for rank in range(max(1, minrank), maxrank):
+            self._index(runners.RankRunner(rank))
 
-        try:
-            for rank in range(max(1, minrank), maxrank):
-                self._index(runners.RankRunner(rank))
-
-            if maxrank == 30:
-                self._index(runners.RankRunner(0))
-                self._index(runners.InterpolationRunner(), 20)
-                self._index(runners.RankRunner(30), 20)
-            else:
-                self._index(runners.RankRunner(maxrank))
-        finally:
-            self._close_connections()
+        if maxrank == 30:
+            self._index(runners.RankRunner(0))
+            self._index(runners.InterpolationRunner(), 20)
+            self._index(runners.RankRunner(30), 20)
+        else:
+            self._index(runners.RankRunner(maxrank))
 
 
     def index_postcodes(self):
@@ -111,12 +152,8 @@ class Indexer:
         """
         LOG.warning("Starting indexing postcodes using %s threads", self.num_threads)
 
-        self._setup_connections()
+        self._index(runners.PostcodeRunner(), 20)
 
-        try:
-            self._index(runners.PostcodeRunner(), 20)
-        finally:
-            self._close_connections()
 
     def update_status_table(self):
         """ Update the status in the status table to 'indexed'.
@@ -147,48 +184,20 @@ class Indexer:
                 with conn.cursor(name='places') as cur:
                     cur.execute(runner.sql_get_objects())
 
-                    next_thread = self.find_free_thread()
-                    while True:
-                        places = [p[0] for p in cur.fetchmany(batch)]
-                        if not places:
-                            break
+                    with WorkerPool(self.dsn, self.num_threads) as pool:
+                        while True:
+                            places = [p[0] for p in cur.fetchmany(batch)]
+                            if not places:
+                                break
 
-                        LOG.debug("Processing places: %s", str(places))
-                        thread = next(next_thread)
+                            LOG.debug("Processing places: %s", str(places))
+                            worker = pool.next_free_worker()
 
-                        thread.perform(runner.sql_index_place(places))
-                        progress.add(len(places))
+                            worker.perform(runner.sql_index_place(places))
+                            progress.add(len(places))
 
-            conn.commit()
+                        pool.finish_all()
 
-        for thread in self.threads:
-            thread.wait()
+                conn.commit()
 
         progress.done()
-
-    def find_free_thread(self):
-        """ Generator that returns the next connection that is free for
-            sending a query.
-        """
-        ready = self.threads
-        command_stat = 0
-
-        while True:
-            for thread in ready:
-                if thread.is_done():
-                    command_stat += 1
-                    yield thread
-
-            # refresh the connections occasionaly to avoid potential
-            # memory leaks in Postgresql.
-            if command_stat > 100000:
-                for thread in self.threads:
-                    while not thread.is_done():
-                        thread.wait()
-                    thread.connect()
-                command_stat = 0
-                ready = self.threads
-            else:
-                ready, _, _ = select.select(self.threads, [], [])
-
-        assert False, "Unreachable code"
index ee9c6c7e99f8cc87b7ce159dfe0c5e6f9fee4b39..6692eba61d349b8908415d793078fba17b0db3af 100644 (file)
@@ -5,7 +5,7 @@ import itertools
 import psycopg2
 import pytest
 
-from nominatim.indexer.indexer import Indexer
+from nominatim.indexer import indexer
 
 class IndexerTestDB:
 
@@ -111,7 +111,7 @@ def test_index_all_by_rank(test_db, threads):
     assert 31 == test_db.placex_unindexed()
     assert 1 == test_db.osmline_unindexed()
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
     idx.index_by_rank(0, 30)
 
     assert 0 == test_db.placex_unindexed()
@@ -150,7 +150,7 @@ def test_index_partial_without_30(test_db, threads):
     assert 31 == test_db.placex_unindexed()
     assert 1 == test_db.osmline_unindexed()
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
     idx.index_by_rank(4, 15)
 
     assert 19 == test_db.placex_unindexed()
@@ -170,7 +170,7 @@ def test_index_partial_with_30(test_db, threads):
     assert 31 == test_db.placex_unindexed()
     assert 1 == test_db.osmline_unindexed()
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
     idx.index_by_rank(28, 30)
 
     assert 27 == test_db.placex_unindexed()
@@ -191,7 +191,7 @@ def test_index_boundaries(test_db, threads):
     assert 37 == test_db.placex_unindexed()
     assert 1 == test_db.osmline_unindexed()
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
     idx.index_boundaries(0, 30)
 
     assert 31 == test_db.placex_unindexed()
@@ -209,14 +209,15 @@ def test_index_postcodes(test_db, threads):
     for postcode in range(32000, 33000):
         test_db.add_postcode('us', postcode)
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
     idx.index_postcodes()
 
     assert 0 == test_db.scalar("""SELECT count(*) FROM location_postcode
                                   WHERE indexed_status != 0""")
 
 
-def test_index_full(test_db):
+@pytest.mark.parametrize("analyse", [True, False])
+def test_index_full(test_db, analyse):
     for rank in range(4, 10):
         test_db.add_admin(rank_address=rank, rank_search=rank)
     for rank in range(31):
@@ -225,10 +226,23 @@ def test_index_full(test_db):
     for postcode in range(1000):
         test_db.add_postcode('de', postcode)
 
-    idx = Indexer('dbname=test_nominatim_python_unittest', 4)
-    idx.index_full()
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', 4)
+    idx.index_full(analyse=analyse)
 
     assert 0 == test_db.placex_unindexed()
     assert 0 == test_db.osmline_unindexed()
     assert 0 == test_db.scalar("""SELECT count(*) FROM location_postcode
                                   WHERE indexed_status != 0""")
+
+
+@pytest.mark.parametrize("threads", [1, 15])
+def test_index_reopen_connection(test_db, threads, monkeypatch):
+    monkeypatch.setattr(indexer.WorkerPool, "REOPEN_CONNECTIONS_AFTER", 15)
+
+    for _ in range(1000):
+        test_db.add_place(rank_address=30, rank_search=30)
+
+    idx = indexer.Indexer('dbname=test_nominatim_python_unittest', threads)
+    idx.index_by_rank(28, 30)
+
+    assert 0 == test_db.placex_unindexed()