Fixed performance pack writing tests. As they are actually depent on the database (as streams have to be decompressed, it should be redesigned to have multiple database implementations)

Author: Byron

git/test/performance/db/test_packedodb_pure.py

@@ -1,7 +1,83 @@
+# Copyright (C) 2010, 2011 Sebastian Thiel (byronimo@gmail.com) and contributors
+#
+# This module is part of GitDB and is released under
+# the New BSD License: http://www.opensource.org/licenses/bsd-license.php
 from packedodb_impl import TestPurePackedODBPerformanceBase
 from git.db.py.pack import PurePackedODB
 
+from git.stream import NullStream
+
+from git.pack import PackEntity
+
+import os
+import sys
+
+from time import time
+from nose import SkipTest
+
+
+class CountedNullStream(NullStream):
+	__slots__ = '_bw'
+	def __init__(self):
+		self._bw = 0
+		
+	def bytes_written(self):
+		return self._bw
+		
+	def write(self, d):
+		self._bw += NullStream.write(self, d)
+	
+
 class TestPurePackedODB(TestPurePackedODBPerformanceBase):
 	#{ Configuration
 	PackedODBCls = PurePackedODB
 	#} END configuration
+	
+	def test_pack_writing(self):
+		# see how fast we can write a pack from object streams.
+		# This will not be fast, as we take time for decompressing the streams as well
+		ostream = CountedNullStream()
+		pdb = self.ropdb
+		
+		ni = 5000
+		count = 0
+		total_size = 0
+		st = time()
+		objs = list()
+		for sha in pdb.sha_iter():
+			count += 1
+			objs.append(pdb.stream(sha))
+			if count == ni:
+				break
+		#END gather objects for pack-writing
+		elapsed = time() - st
+		print >> sys.stderr, "PDB Streaming: Got %i streams by sha in in %f s ( %f streams/s )" % (ni, elapsed, ni / elapsed)
+		
+		st = time()
+		PackEntity.write_pack(objs, ostream.write)
+		elapsed = time() - st
+		total_kb = ostream.bytes_written() / 1000
+		print >> sys.stderr, "PDB Streaming: Wrote pack of size %i kb in %f s (%f kb/s)" % (total_kb, elapsed, total_kb/elapsed)
+		
+	
+	def test_stream_reading(self):
+		raise SkipTest("This test was only used for --with-profile runs")
+		pdb = self.ropdb
+		
+		# streaming only, meant for --with-profile runs
+		ni = 5000
+		count = 0
+		pdb_stream = pdb.stream
+		total_size = 0
+		st = time()
+		for sha in pdb.sha_iter():
+			if count == ni:
+				break
+			stream = pdb_stream(sha)
+			stream.read()
+			total_size += stream.size
+			count += 1
+		elapsed = time() - st
+		total_kib = total_size / 1000
+		print >> sys.stderr, "PDB Streaming: Got %i streams by sha and read all bytes totallying %i KiB ( %f KiB / s ) in %f s ( %f streams/s )" % (ni, total_kib, total_kib/elapsed , elapsed, ni / elapsed)
+