How to configure apache web server to server more than 2000 TPS
How do you do load testing and capacity planning for web sites?
How do I sudo a command in a script without being asked for a password? I want to turn my system on automatically every day. So I use the below code in my Python script, but sudo asks me for a password every time:  os.system('sudo sh -c "echo date \'+%s\' -d \'+ \        24 hours\' &gt; /sys/class/rtc/rtc0/wakealarm"')   How can I run this script without sudo asking for the password every time? Conservation law of energy and Big Bang? Did the law of conservation of energy apply to the earliest moments of the Big Bang? If so, what theoretical physics supports this?   I hear that Einstein's theory of relativity disputes the law of conservation of energy- so does that mean the law is false, or only some aspect of it? I have a nominal variable (different topics of conversation, coded as topic0=0 etc) and a number of scale variables (DV) such as the length of a conversation.   How can I derive correlations between the nominal and scale variables? How is consensus determined on Meta sites? On our main sites &quot;the best answer&quot; is  as the superposition of the highest voted answer and the accepted answer.  Truth be told, the system is rather insistent on allowing multiple &quot;right answers&quot; and that's one of its strengths: you can be the judge of who you believe. But that doesn't always translate well on the per-site metas, which serve as a sort of policy-creation body.  People who are active on meta help decide how policies are enforced on the main site.  Moderators who have ♦-powers tend to take mandates on meta very seriously.  , accepted answers to meta-questions are no different than any other answer.  Does that leave just votes to determine consensus? Closely related: Not everyone participates on meta-sites.  It can be hard to tell if enough people have looked and voted on questions for real consensus to be declared.  Size of the site determines how many people could be voting on questions.  What counts as a quorum? Finally, sometimes people change their minds about a meta-question, but, , it's not really possible to change one's mind without a pointless edit to someone else's answer.  When should meta-questions be revisited?  On graduated sites, ♦ moderators are elected, which makes them representatives of the active participants, but on beta sites, we are appointed.  It's doubly pressing for beta sites to determine &quot;the will of the people&quot; since part of the point of a beta is to get a working policy framework in place before electing permanent moderators. I'm interested in figuring out how sites already answer these questions and what might be done network-wide to make discovering consensus a little bit easier.  N.B.: Obviously this assumes that consensus matters.  It does to me when I'm making my decisions and I suspect it matters to others.  But that isn't to say that it always makes a difference.  I'm really not interested in answers that hope to use this question as a grindstone for all the axes stored up against certain people who have made unpopular decisions and have the power to make those decisions stick.  Feel free to ask your own question(s).  (Thank you.) How can I prevent URLDownloadToFile from retrieving from the cache? I am using URLDownloadToFile to retrieve a file from a website. Subsequent calls return the original file rather than an updated version.  I assume it is retrieving a cached version. The dialog box in question here is the one you get with the context menu option "open with other applications". Wine seems to have inserted more than a dozen or so entries for each application I install, which makes it a pain to find the correct application:     What can I do to remove the duplicates?     Update: Neither of the two solutions really work. The bug is interesting, but the symptoms does not match my problem (I'm not having problem with uninstalling applications, but rather the things that are inserted after installing them), and with the other one, all references to the Wine application are removed, which actually makes the problem worse (although it may be an acceptable solution if nothing else can be found). So this is still an open question; any takers? Can I install Ubuntu inside Windows? Ubuntu 12.04 won't come with the Windows Installer (Wubi) pre-added. But is there any way to install 12.04 using Wubi? Is there a replacement for unistd.h for Windows (Visual C)? I'm porting a relatively simple console program written for Unix to the Windows platform (). All the source files include "unistd.h", which doesn't exist.  Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'. I know I can replace the random functions, and I'm pretty sure I can find/hack-up a getopt implementation.    But I'm sure others have run into the same challenge.  My question is: is there a port of "unistd.h" to Windows? At least one containg those functions which do have a native Windows implementation - I don't need pipes or forking.  EDIT:  I know I can create my very own "unistd.h" which contains replacements for the things I need - especially in this case, since it is a limited set. But since it seems like a common problem, I was wondering if someone had done the work already for a bigger subset of the functionality.  Switching to a different compiler or environment isn't possible at work - I'm stuck with Visual Studio. Overheating results in system shutdown How can I get a debug log for the sites guest user/public profile? [updated for Spring 18] Shadows along edges of mesh in 3D View $n$ choose $k$ where $n$ is less than $k$ I've just executed a long-running process from the bash prompt. In hindsight, I wish I'd run time on it, or noted down the time at which I kicked it off.  Is there any way of getting this information retrospectively? The .bash_history doesn't seem to include timestamps.  In my particular case it's Mac OS X, but I'm interested in general Unix/Linux solutions.  To clarify, the process has now completed, and I'd prefer not to run it again unless absolutely necessary! If I want to use objects as the keys for a Dictionary, what methods will I need to override to make them compare in a specific way?  Say I have a a class which has properties:  class Foo {     public string Name { get; set; }     public int FooID { get; set; }      // elided }    And I want to create a:  Dictionary&lt;Foo, List&lt;Stuff&gt;&gt;   I want Foo objects with the same FooID to be considered the same group.  Which methods will I need to override in the Foo class?  To summarize: I want to categorize Stuff objects into lists, grouped by Foo objects. Stuff objects will have a FooID to link them to their category. jquery disable form submit on enter In Breaking Bad, Walter White chooses to go by Heisenberg. I know that there has to be some significance behind both why Walt chose the name and why the writers chose that name as opposed to any other physicist's. It would make sense for it to have something to do with Heisenberg's uncertainty principle, which postulates (in broad strokes) that any system is fundamentally unstable on a short enough time frame. The connection between that and Walt's specific character eludes me though. In ubuntu 11.04 there was a workaround using gconf-editor and setting key /apps/gnome_settings_daemon/plugins/xrandr/active to false.  However there is no such key in gconf-manager using ubuntu 11.10 (gnome 3). What is the maximum or minimum tire width I can fit on my bicycle Converting a DC motor to a generator Can ANY DC motor become a generator if torque is applied to the shaft? example:   And by any, I mean the really cheap ones too.  Or is there a specific type of motor (of which I do not know the name) that can work in both directions (battery to power the shaft OR torque-on-shaft to create a voltage difference between the terminals). Correct spelling of Polish surname Dziubenofska? My Polish grandmothers last name was Dziubenofska, but I know that's not how it is spelt! I'm looking for the proper spelling.   Can you help find it for me?  She came over to Ellis Island and they changed it on her to dziuk. This is only a prefix to the full name.