Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail From: Ian Kelly Newsgroups: comp.lang.python Subject: Re: Reason for not allowing import twice but allowing reload() Date: Tue, 1 Mar 2016 15:29:46 -0700 Lines: 32 Message-ID: References: <645cdd46-d4a4-49b3-a0d8-848608d70d73@googlegroups.com> <56d57aa4$0$1586$c3e8da3$5496439d@news.astraweb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: news.uni-berlin.de goZWHazU74aPMTIndNreoQiekstB7t8KPHYvEj3LfEsw== Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.115 X-Spam-Level: * X-Spam-Evidence: '*H*': 0.77; '*S*': 0.00; 'modify': 0.04; 'subject:()': 0.09; 'weeks,': 0.09; 'subject:not': 0.11; 'wed,': 0.15; '2016': 0.16; 'downtime': 0.16; 'downtime.': 0.16; 'received:io': 0.16; 'received:psf.io': 0.16; 'subject:import': 0.16; 'wrote:': 0.16; 'memory': 0.17; 'changes': 0.20; 'am,': 0.23; 'leave': 0.23; 'minutes.': 0.23; 'header:In-Reply-To:1': 0.24; 'script': 0.25; "i've": 0.25; 'chris': 0.26; 'comfortable': 0.27; 'message-id:@mail.gmail.com': 0.27; 'module.': 0.27; 'tend': 0.27; 'regular': 0.29; 'long.': 0.29; 'restart': 0.29; "i'm": 0.30; 'certainly': 0.30; 'connections': 0.30; 'up.': 0.32; 'maybe': 0.33; 'though.': 0.33; 'tue,': 0.34; 'weeks': 0.34; 'running': 0.34; 'received:google.com': 0.35; 'so,': 0.35; 'next': 0.35; 'clear': 0.35; "isn't": 0.35; 'problem.': 0.35; 'but': 0.36; 'received:209.85': 0.36; 'to:addr:python-list': 0.36; 'pm,': 0.36; 'subject:: ': 0.37; 'being': 0.37; 'received:209.85.213': 0.37; 'difference': 0.38; 'version': 0.38; 'received:209': 0.38; 'enough': 0.39; 'to:addr:python.org': 0.40; 'your': 0.60; 'skip:u 10': 0.61; 'caused': 0.61; 'real': 0.62; 'back': 0.62; 'making': 0.62; 'matter': 0.63; 'more': 0.63; 'day.': 0.63; 'times': 0.63; 'minutes': 0.64; 'within': 0.64; 'between': 0.65; 'mar': 0.65; 'importantly,': 0.66; 'night': 0.67; 'shortly': 0.72; 'ago),': 0.84; 'off,': 0.84; 'to:name:python': 0.84; 'updates,': 0.84; 'uptime': 0.84; 'game,': 0.91 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=k5mjJf5+ufoEkj5NFS8Au4A4I84QUhlmO4qufFqbhYk=; b=pv1WLo2feRqxlgwpfadhZJIB/VqLWYyLabRa1cHcTgQE5wGIfCMAejIg07cjPSqXou bB5m8xH6s9/wH1KEfgR4z5RivlJT6dJjjBL2irKeyHCnopI6PYo9jCKYPnwn0NMyUo36 Kj3kYQ7Au8OgE22NGuFKYFfTIjmyKbJVx7IG1WzC9/BB8IhzREMqXCbBfpUccX9YDLxF h5x7G11tfu7Ky49dd7wWv3wrjVKSskSGCLgoJJBz/+XOjC6zlZLiEotMbySNv2B7FP/+ CX2DUo1fhtdZTp8P3Tyfa/FTjcOtnC7pBWJquLxhGBv8Yhom5jCQCnnnme4JwPv+4FbQ wP4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=k5mjJf5+ufoEkj5NFS8Au4A4I84QUhlmO4qufFqbhYk=; b=i4FPqj1u3OV9ytAKE69S1MYhdu5MnQQNTTnXk8ssIy+JBRsZPRzB/+LipLN3/dI3jA Vwcwea51shdU9D/isfIOcBtp2z8F5XCmxOSBpqfEkT03EimKf0w2vRz1Ytp7WxJeAfSP oHzlRw0gfyJvJ6WZOHKoTF9b8oOAOuOlenWEOBlPxE8GATTIQfkCqSO+Je8dNc+fUOOB RcIgzYOUtcqClKQXkZmcDLoVs5JLH6F/SNL4vLQ8rcdUZxEZIt2GuHkq5+JHE3x6AdOu tRtO9ovcQZlFLObaYLZhhjoveV0QcenOIt1FJUFLJLsqOASxp67rnpHaUrZ98SsS56BW sNYw== X-Gm-Message-State: AD7BkJJyZk8tqQb/qYf9i14bBvPQQUKOz9qkH3hxUwjffV9WOgAO584LKJgFz48psd3Om3zaWuC7x/mXVYJ2gQ== X-Received: by 10.50.112.10 with SMTP id im10mr1441532igb.93.1456871426197; Tue, 01 Mar 2016 14:30:26 -0800 (PST) In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com comp.lang.python:103824 On Tue, Mar 1, 2016 at 3:02 PM, Chris Angelico wrote: > On Wed, Mar 2, 2016 at 8:53 AM, Ian Kelly wrote: >> I have a hard time understanding the appeal of super-long uptimes. I'm not >> even comfortable running a single kernel version that long. What's so awful >> about 5 minutes of announced downtime in the middle of the night once a >> month while the system restarts? > > It kicks connections off, which may not matter to web sites, but it > matters to servers that are designed for long-running connections. But > more importantly, five minutes once a month isn't enough to do all > your updates - so a live-update system would be required even with a > regular monthly reset. I tend to have announced outages for kernel > updates and such (eg a couple weeks ago), but in between, I want to be > able to keep everything going, even though I'm making changes. > > Maybe I don't get to a year all that often (from memory, I think I've > just twice achieved >1y uptime), but I certainly have multi-day > uptimes, despite making changes multiple times a day. And I want to be > able to deploy changes in the middle of a game, not leave off until > the next scheduled downtime. So, yes, I need to be able to modify an > already-imported module. I certainly understand the value of being able to work on a mudlib without having to restart the mud. There's a big difference between that and clocking a year of uptime just because you can, though. The MUD that I used to play had scheduled restarts every 2-4 weeks, not to perform updates, but just to restart the process and clear out memory leaks. This never caused any real problem. You knew that it was coming because it was announced, and you took a break for a couple of minutes. If you were AFK, then your auto-login script reconnected you within shortly after the MUD came back up.