From a725446766ae9e4b34f34c3f19e50c4df89b7e41 Mon Sep 17 00:00:00 2001 From: Zac Medico Date: Fri, 20 Feb 2009 23:37:13 +0000 Subject: [PATCH] When loading vdb_metadata.pickle inside vardbapi._aux_cache_init(), in order to avoid an extreme performance issue, disable buffering when opening the file under python-3.0. Unfortunately, performance is still poor relative to python-2.x, but buffering makes it much worse. svn path=/main/trunk/; revision=12665 --- pym/portage/dbapi/vartree.py | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py index 4877e68a9..cfabad844 100644 --- a/pym/portage/dbapi/vartree.py +++ b/pym/portage/dbapi/vartree.py @@ -35,6 +35,7 @@ from portage.cache.mappings import slot_dict_class import os, re, shutil, stat, errno, copy, subprocess import logging import shlex +import sys from itertools import izip try: @@ -1044,8 +1045,15 @@ class vardbapi(dbapi): def _aux_cache_init(self): aux_cache = None + open_kwargs = {} + if sys.hexversion >= 0x3000000: + # Buffered io triggers extreme performance issues in + # Unpickler.load() (problem observed with python-3.0.1). + # Unfortunately, performance is still poor relative to + # python-2.x, but buffering makes it much worse. + open_kwargs["buffering"] = 0 try: - f = open(self._aux_cache_filename, 'rb') + f = open(self._aux_cache_filename, mode='rb', **open_kwargs) mypickle = pickle.Unpickler(f) aux_cache = mypickle.load() f.close() -- 2.26.2