我正在将一个中型 Django 1.4.2 应用程序迁移到新的基础设施，并尝试在新的、非常强大的硬件上优化系统的性能。我正在使用 django-debug-toolbar 以及基于热点的分析中间件来定位瓶颈，目前很难理解我从不同来源获得的执行时间值的差异。
例如，如果我向应用程序中的 URL 发出单个请求，并且将其映射到一个相当简单的视图，以下是我得到的时间：
Nginx 1.2.5 - 0.409s：
10.10.1.101 151a6b897ee788499fd19d6531befaac [17/Dec/2012:23:43:53 -0800] 200 0.409 1633 "GET /product/150138/?prof HTTP/1.1" "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.97 Safari/537.11"
uWSGI 1.4.2（64 位）- 387 毫秒：
Mon Dec 17 23:27:50 2012 151a6b897ee788499fd19d6531befaac GET mysite.com/product/150138/?prof HTTP/1.1 200 387ms
Django 调试工具栏 - 112.452 毫秒：
Resource Value
User CPU time 84.005 msec
System CPU time 4.001 msec
Total CPU time 88.006 msec
Elapsed time 112.452 msec
Context switches 33 voluntary, 10 involuntary
SQL: 16.42 ms (8 queries)
分析中间件 - 0.132 秒：
113020 function calls (110410 primitive calls) in 0.132 seconds
Ordered by: internal time, call count
ncalls tottime percall cumtime percall filename:lineno(function)
10232 0.046 0.000 0.046 0.000 /opt/myenv/lib/python2.7/posixpath.py:60(join)
10187 0.032 0.000 0.040 0.000 /opt/myenv/lib/python2.7/posixpath.py:130(islink)
1396/1354 0.022 0.000 0.120 0.000 /opt/myenv/lib/python2.7/posixpath.py:355(realpath)
2682 0.018 0.000 0.018 0.000 /opt/myenv/lib/python2.7/posixpath.py:312(normpath)
8 0.016 0.002 0.016 0.002 /opt/myenv/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/base.py:50(execute)
1568 0.010 0.000 0.022 0.000 /usr/lib/python2.7/inspect.py:440(getsourcefile)
214 0.009 0.000 0.138 0.001 /usr/lib/python2.7/inspect.py:472(getmodule)
23 0.008 0.000 0.008 0.000 /opt/myenv/lib/python2.7/linecache.py:68(updatecache)
1544 0.007 0.000 0.007 0.000 /opt/myenv/lib/python2.7/genericpath.py:15(exists)
8 0.005 0.001 0.205 0.026 /opt/myenv/lib/python2.7/site-packages/debug_toolbar/utils/tracking/db.py:85(execute)
10187 0.005 0.000 0.007 0.000 /opt/myenv/lib/python2.7/stat.py:55(S_ISLNK)
458 0.005 0.000 0.008 0.000 /opt/myenv/lib/python2.7/site-packages/django/template/base.py:673(__init__)
4 0.004 0.001 0.005 0.001 /opt/myenv/lib/python2.7/site-packages/memcache.py:965(_recv_value)
395 0.004 0.000 0.011 0.000 /opt/myenv/lib/python2.7/site-packages/django/template/base.py:524(__init__)
7243 0.004 0.000 0.004 0.000 /usr/lib/python2.7/inspect.py:51(ismodule)
4078 0.003 0.000 0.003 0.000 /opt/myenv/lib/python2.7/posixpath.py:51(isabs)
114/10 0.003 0.000 0.028 0.003 /opt/myenv/lib/python2.7/site-packages/django/template/base.py:234(parse)
2504 0.003 0.000 0.021 0.000 /opt/myenv/lib/python2.7/posixpath.py:341(abspath)
803 0.002 0.000 0.003 0.000 /opt/myenv/lib/python2.7/site-packages/django/template/base.py:200(create_token)
6 0.002 0.000 0.002 0.000 /opt/myenv/lib/python2.7/site-packages/django/db/models/options.py:388(_fill_related_objects_cache)
10187 0.002 0.000 0.002 0.000 /opt/myenv/lib/python2.7/stat.py:24(S_IFMT)
621 0.002 0.000 0.004 0.000 /opt/myenv/lib/python2.7/site-packages/django/utils/functional.py:170(wrapper)
1806 0.002 0.000 0.005 0.000 /usr/lib/python2.7/inspect.py:398(getfile)
6224 0.002 0.000 0.002 0.000 /usr/lib/python2.7/string.py:220(lower)
1150 0.002 0.000 0.027 0.000 /usr/lib/python2.7/inspect.py:460(getabsfile)
394/273 0.002 0.000 0.002 0.000 /opt/myenv/lib/python2.7/site-packages/django/template/context.py:49(__getitem__)
214 0.002 0.000 0.154 0.001 /usr/lib/python2.7/inspect.py:518(findsource)
1 0.002 0.002 0.005 0.005 /opt/myenv/lib/python2.7/site-packages/django/core/urlresolvers.py:237(_populate)
505 0.002 0.000 0.002 0.000 /opt/myenv/lib/python2.7/site-packages/django/utils/text.py:320(smart_split)
59/21 0.002 0.000 0.004 0.000 /opt/myenv/lib/python2.7/sre_parse.py:379(_parse)
59 0.001 0.000 0.006 0.000 /opt/myenv/lib/python2.7/site-packages/django/templatetags/i18n.py:281(do_translate)
10 0.001 0.000 0.005 0.000 /opt/myenv/lib/python2.7/site-packages/django/template/base.py:188(tokenize)
518/88 0.001 0.000 0.003 0.000 /usr/lib/python2.7/copy.py:145(deepcopy)
214 0.001 0.000 0.160 0.001 /opt/myenv/lib/python2.7/site-packages/debug_toolbar/utils/__init__.py:101(getframeinfo)
446 0.001 0.000 0.001 0.000 /opt/myenv/lib/python2.7/site-packages/django/utils/text.py:364(unescape_string_literal)
---- By file ----
tottime
43.4% 0.102 /opt/myenv/lib/python2.7/posixpath.py
13.2% 0.031 /usr/lib/python2.7/inspect.py
9.4% 0.022 /opt/myenv/lib/python2.7/site-packages/django/template/base.py
6.8% 0.016 /opt/myenv/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/base.py
3.4% 0.008 /opt/myenv/lib/python2.7/linecache.py
3.0% 0.007 /opt/myenv/lib/python2.7/stat.py
3.0% 0.007 /opt/myenv/lib/python2.7/genericpath.py
2.1% 0.005 /opt/myenv/lib/python2.7/site-packages/debug_toolbar/utils/tracking/db.py
1.7% 0.004 /opt/myenv/lib/python2.7/sre_parse.py
1.7% 0.004 /opt/myenv/lib/python2.7/site-packages/memcache.py
1.3% 0.003 /opt/myenv/lib/python2.7/site-packages/django/utils/text.py
1.3% 0.003 /opt/myenv/lib/python2.7/site-packages/django/core/urlresolvers.py
0.9% 0.002 /usr/lib/python2.7/string.py
0.9% 0.002 /opt/myenv/lib/python2.7/site-packages/django/utils/regex_helper.py
0.9% 0.002 /opt/myenv/lib/python2.7/site-packages/django/utils/functional.py
0.9% 0.002 /opt/myenv/lib/python2.7/site-packages/django/template/context.py
0.9% 0.002 /opt/myenv/lib/python2.7/site-packages/django/db/models/options.py
0.9% 0.002 /opt/myenv/lib/python2.7/site-packages/debug_toolbar/utils/__init__.py
0.4% 0.001 /usr/lib/python2.7/copy.py
0.4% 0.001 /opt/myenv/source/portal/myenv/views/__init__.py
0.4% 0.001 /opt/myenv/lib/python2.7/sre_compile.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/utils/safestring.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/utils/importlib.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/utils/encoding.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/templatetags/i18n.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/template/loaders/app_directories.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/template/defaulttags.py
0.4% 0.001 /opt/myenv/lib/python2.7/site-packages/django/db/models/base.py
0.4% 0.001 /opt/myenv/lib/python2.7/encodings/utf_8.py
0.0% 0.000
0.0% 0.000 /usr/lib/python2.7/uuid.py
0.0% 0.000 /usr/lib/python2.7/urllib.py
0.0% 0.000 /usr/lib/python2.7/threading.py
0.0% 0.000 /usr/lib/python2.7/socket.py
0.0% 0.000 /usr/lib/python2.7/pprint.py
0.0% 0.000 /usr/lib/python2.7/multiprocessing/process.py
0.0% 0.000 /usr/lib/python2.7/logging/handlers.py
0.0% 0.000 /usr/lib/python2.7/logging/__init__.py
0.0% 0.000 /usr/lib/python2.7/gettext.py
0.0% 0.000 /usr/lib/python2.7/functools.py
如您所见，django-debug-toolbar 和 hotshots 分析中间件的时间非常接近。
在 Django 渲染模板后，什么可能导致 uWSGI 处理额外的约 250 毫秒的请求？我尝试在 uWSGI 中启用分析器选项，但它会为数十万次调用生成信息，因此很难使用。
任何建议表示赞赏。