Path: csiph.com!usenet.pasdenom.info!aioe.org!news.stack.nl!newsfeed.xs4all.nl!newsfeed2a.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'from:addr:yahoo.co.uk': 0.04; 'cpython': 0.05; '(python': 0.07; 'debugging': 0.07; 'decorator': 0.09; 'facts': 0.09; 'lawrence': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'second.': 0.09; 'seemed': 0.09; 'statements': 0.09; 'python': 0.11; 'language.': 0.14; 'merely': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'sorts': 0.16; 'unresponsive': 0.16; 'language': 0.16; 'wrote:': 0.18; 'bit': 0.19; 'module': 0.19; 'seems': 0.21; 'print': 0.22; 'header:User-Agent:1': 0.23; '---': 0.24; 'logging': 0.26; 'second': 0.26; 'header:X -Complaints-To:1': 0.27; 'header:In-Reply-To:1': 0.27; 'function': 0.29; "doesn't": 0.30; 'went': 0.31; 'code': 0.31; 'that.': 0.31; 'core': 0.34; 'something': 0.35; 'but': 0.35; 'there': 0.35; 'really': 0.36; 'seconds': 0.37; 'two': 0.37; 'to:addr:python- list': 0.38; 'to:addr:python.org': 0.39; 'enough': 0.39; 'skip:p 20': 0.39; 'received:org': 0.40; 'removing': 0.60; 'free': 0.61; 'affect': 0.61; 'new': 0.61; 'viruses': 0.61; 'first': 0.61; 'protection': 0.63; 'our': 0.64; '2-3': 0.68; 'antivirus': 0.68; 'slowed': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Mark Lawrence Subject: Re: print statements and profiling a function slowed performance Date: Thu, 26 Jun 2014 20:27:48 +0100 References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: host-92-18-5-57.as13285.net User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 In-Reply-To: X-Antivirus: avast! (VPS 140626-1, 26/06/2014), Outbound message X-Antivirus-Status: Clean X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 31 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1403810884 news.xs4all.nl 2904 [2001:888:2000:d::a6]:37367 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:73633 On 26/06/2014 19:44, CM wrote: > Huh. I learned two new Python facts this week: > > 1. print statements were slowing down my code enough to > really notice a particular transition. It went from about > 2-3 seconds to a bit under 1 second. What at first seemed > unresponsive now seems almost snappy. The only difference > was removing a lot of print statements I had used for > debugging (Python 2.5, on a single core 1.97 Ghz machine). > > 2. Merely having a cPython decorator for profiling a > function significantly slowed down performance...again, > from a about 2 seconds to just under a second (~1 second > doesn't seem much but these sorts of delays do affect > user experience). There is something ironic or > Heisenbergian about that. > 3. use the logging module :) -- My fellow Pythonistas, ask not what our language can do for you, ask what you can do for our language. Mark Lawrence --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com