Search Results

Search found 1576 results on 64 pages for 'brian wilson'.

Page 56/64 | < Previous Page | 52 53 54 55 56 57 58 59 60 61 62 63  | Next Page >

  • Samsung a-t-il triché sur les benchmarks pour le Galaxy S4 ? Les performances de l'Exynos 5 remises en cause après des tests

    Samsung : les Galaxy S4 affichent des performances élevées pour les benchmarks Mais moindres pour les autres applicationsTout a débuté avec le post d'un utilisateur mécontent sur le site Beyond3d après qu'il ait réalisé des bancs d'essai pour le GPU de son Galaxy S4. Pendant les essais, l'utilisateur constate que le GPU de son smartphone tourne à 532 Mhz. Cependant, pour toutes les autres applications y compris les jeux (aux résolutions les plus poussées) ce dernier ne tournerait plus qu'à 480 Mhz. « Oh Samsung honte à toi ! » écrira-t-il.Par la suite, Brian Klug et Anand Lal Shimpi, du site web Anandtech, reprennent eux aussi l'expérience de cet utilisateur avec leurs propres smartphones pour en confirmer...

    Read the article

  • Why is Git telling me "Your branch is ahead of 'origin/master' by 11 commits." and how do I get it t

    - by spilth
    I'm a Git newbie. I recently moved a Rails project from Subversion to Git. I followed the tutorial here: http://www.simplisticcomplexity.com/2008/03/05/cleanly-migrate-your-subversion-repository-to-a-git-repository/ I am also using unfuddle.com to store my code. I make changes on my Mac laptop on the train to/from work and then push them to unfuddle when I have a network connection using the following command: git push unfuddle master I use Capistrano for deployments and pull code from the unfuddle repository using the master branch. Lately I've noticed the following message when I run "git status" on my laptop: # On branch master # Your branch is ahead of 'origin/master' by 11 commits. # nothing to commit (working directory clean) And I'm confused as to why. I thought my laptop was the origin... but don't know if either the fact that I originally pulled from Subversion or push to Unfuddle is what's causing the message to show up. How can I: Find out where Git thinks 'origin/master' is? If it's somewhere else, how do I turn my laptop into the 'origin/master'? Get this message to go away. It makes me think Git is unhappy about something. My mac is running Git version 1.6.0.1. When I run git remote show origin as suggested by dbr, I get the following: ~/Projects/GeekFor/geekfor 10:47 AM $ git remote show origin fatal: '/Users/brian/Projects/GeekFor/gf/.git': unable to chdir or not a git archive fatal: The remote end hung up unexpectedly When I run git remote -v as suggested by Aristotle Pagaltzis, I get the following: ~/Projects/GeekFor/geekfor 10:33 AM $ git remote -v origin /Users/brian/Projects/GeekFor/gf/.git unfuddle [email protected]:spilth/geekfor.git Now, interestingly, I'm working on my project in the geekfor directory but it says my origin is my local machine in the gf directory. I believe gf was the temporary directory I used when converting my project from Subversion to Git and probably where I pushed to unfuddle from. Then I believe I checked out a fresh copy from unfuddle to the geekfor directory. So it looks like I should follow dbr's advice and do: git remote rm origin git remote add origin [email protected]:spilth/geekfor.git

    Read the article

  • Where is the node.js file in the stack trace located?

    - by user225189
    Obviously, I'm pretty new to node.js. I'm attempting to debug a node.js application and I see node.js in the stack trace. I would like to put some sys.puts calls in there, but I cannot locate the node.js that is being run by my server. Is there a way to tell where node.js is located? Is there an equivalent to Ruby's FILE in node? Thanks, Brian

    Read the article

  • What the difference between a namespace and a module in F#?

    - by Dave Berk
    I've just started learning F# (with little prior experience with .NET) so forgive me for what is probably a very simple question: What the difference between a namespace and a module in F#? Thanks Dave Edit: Thanks for the answer Brian. That's what I wanted to know. Just a clarification: can you also open a namespace as well (similar to C# using statement)?

    Read the article

  • NHibernate criteria construction

    - by brianberns
    I am trying to recreate something like the following SQL using NHibernate criteria: select Range, count(*) from ( select case when ent.ID between 'A' and 'N' then 'A-M' else 'Other' end as Range from Subject ) tbl group by tbl.Range I am able to create the inner select as follows: session.CreateCriteria<Subject>() .SetProjection( Projections.Conditional( Expression.Between("Name", "A", "N"), Projections.Constant("A-N"), Projections.Constant("Other"))) .List(); However, I can't figure out how to pipe those results into a grouping by row count. Any suggestions? Thanks. -- Brian

    Read the article

  • Separate groups of people based on members

    - by tevch
    I have groups of people. I need to move groups with at least one same member as far as possible from each other. Example: GroupA - John, Bob, Nick GroupB - Jack, Nick GroupC - Brian, Alex, Steve As you can see GroupA and GroupB overlap(they both contain Nick) I need an algorithm to set groups as GroupA-GroupC-GroupB Thank you

    Read the article

  • F# Blogs to follows

    - by AG.
    Hello All, I have recently started learning F#. I was wondering as which are the recommended blogs you guys are currently following in F# community?. I am currently subscribed to "Tomas Petricek", "Brian McNamara" and "Don Syme's". Would love to hear all your recommendations.

    Read the article

  • How do I make a table from a List MVC?

    - by user54197
    I have a List(Name, Item, Group#) that I would like to display in a table. How do I display this data with all the names in the 1st row, item in the 2nd, and group number in the 3rd row. Name: | Jon | Tom | Kate | Brian | Item: | Cup | Hat | Door | Store | Group#:| 2 | 8 | 10 | 154 |

    Read the article

  • Can the Windows Phone 7 Series emulator be made to run on Windows XP?

    - by sweeney
    Well thats all there is to it...is this possible? I understand that officially it's not supported but has anyone figured it out? I have some work to do where XP would be the preferred platform. I would expect that users of the actual device are not required to use Windows 7 so it stands to reason that this can be done. Any poitners in the right direction would be greatly appreciated. Thanks, brian

    Read the article

  • Can the Windows Phone 7 Series emulator be made to run XP?

    - by sweeney
    Well thats all there is to it...is this possible? I understand that officially it's not supported but has anyone figured it out? I have some work to do where XP would be the preferred platform. I would expect that users of the actual device are not required to use Windows 7 so it stands to reason that this can be done. Any poitners in the right direction would be greatly appreciated. Thanks, brian

    Read the article

  • Escapeing values in PDO statements

    - by Pardoner
    Doesn't prepare() escape any quotes(') in a PDO statement? For some reason when I do this: $sql = "INSERT INTO sessions (id, name) VALUES (1,'O'brian')"; $query = $this->connection->prepare($sql); $query->execute(); I get this error: Could not insert record SQLSTATE[42000]: [Microsoft][SQL Server Native Client 10.0][SQL Server]Incorrect syntax near 'brian'. How could this be if I'm using prepare()?

    Read the article

  • Kohana 3: Auth module

    - by Thomas
    Hi, i'm trying to learn the Kohana's Auth module but login method always return false. Controller: <?php defined('SYSPATH') OR die('No Direct Script Access'); class Controller_Auth extends Controller { public function action_index() { if($_POST) { $this->login(); } $this->template = View::factory('login'); echo $this->template; } private function login() { $user = ORM::factory('user'); $data = array('username' => 'wilson', 'password' => '123'); if(!$user->login($data)) { echo 'FAILED!'; } } private function logout() { } } ?> Model: <?php defined('SYSPATH') or die('No direct script access.'); class Model_User extends Model_Auth_User { } ?>

    Read the article

  • Novell Netware 6 and C#

    - by user317744
    Hi, I don't know if anyone has any expertise with Novell Netware or not, but I situation where one of my clients is getting a weird error trying to move a file to a netware share. The situation is pretty complicated but I'll try and outline it as best I can. 1) The application is running as a service 2) The file to be moved is a local file in an accessible location (to the service) 3) The file is being moved with FileInfo.MoveTo(). 4) The MoveTo is throwing an IOException and the message is "a device attached to the system is not functioning". I'm at a loss as to explain what might be happening. On a side note, it seems that running a small test program interactively using the same method (FileInfo.MoveTo) to the same location works fine so it seems to be associated with the service itself. Any help would be hugely greatful. Thanks. Kristofor Wilson

    Read the article

  • JQuery dirtyForm not working on text boxes in ajaxToolkit:TabPanel

    - by dustinson
    I'm a newb to jQ so please forgive my ignorance. I'm using Asa Wilson's plugin jquery.dirtyform.js to prompt a user of unsaved changes before they nav away from a page (ASP.Net C# 3.5). It basically loops through all controls and appends a class and handler to each input. Controls w/i an ajaxToolkit:TabPanel are ignored, unfortunately. I'd appreciate if anyone knows of this type of error and how to resolve it short of manually manipulating each control (as I have this logic in the master page). Thank you.

    Read the article

  • jQuery autocomplete function, how to add support for words not available in the database yet?

    - by Lyon
    Hi, I'm looking to implement a tag system like how SO uses on their site, where users can specify multiple tag words. However, on top of all the other autocomplete functions available as jquery plugins, I also want to allow users to enter new words not in the database. Does anyone know of any plugin that can do that? Or if there isn't, how one can add that functionality to an existing autocomplete function? I'm exploring Drew Wilson's autosuggest plugin at the moment, as it supports multiple tags well: http://code.drewwilson.com/entry/autosuggest-jquery-plugin Any help appreciated! Thanks :)

    Read the article

  • Is there an "extended" UIHint attribute to apply CSS styles for DisplayFor - EditorFor templates?

    - by AJ
    Intro: After reading Brad Wilson Metadata series and searching unsuccesfully on google, I was wondering: Question: Has any OS project / code been created that allows you to tag CSS styles in the Meta information, for example in my (buddy) Model, I want to be able to decorate a property with multiple CSS styles (a single style you can fake with UIHint, I want to set many possible styles - and be able to "cross-utilise") eg. public class MyModel { [DisplayCssHint("h5")] [DisplayCssHint("color:#777;")] [EditorCssHint(".myCoolTextClass")] [EditorCssHint(".myOtherCoolTextClass")] public string Title{ get;set; } [DisplayCssHint(".normaltext")] [EditorCssHint(".myCoolTextClass")] [EditorCssHint(".myOtherCoolTextClass")] public string Message {get;set;} } Thoughts: I know that this does not seem like a logical place to put styling information, however as it is metadata and is discriptive... besides it would be nice to do this while prototyping - (especially being able to apply class styles and extending it further - to generate .Less files would really be cool! more to the point I would hate to write it, if its already been done ;). Any links/pointers/idea's would be appreciated. Thanks,

    Read the article

  • How do I return pure XML from asmx web service?

    - by User
    I want an asmx webservice with a method GetPeople() that returns the following XML (NOT a SOAP response): <People> <Person> <FirstName>Sara</FirstName> <LastName>Smith</LastName> </Person> <Person> <FirstName>Bill</FirstName> <LastName>Wilson</LastName> </Person> <People/> How can I do this?

    Read the article

  • toString() Method question

    - by cdominguez13
    I've been working on this assignemnt here's code: public class Student { private String fname; private String lname; private String studentId; private double gpa; public Student(String studentFname,String studentLname,String stuId,double studentGpa) { fname = studentFname; lname = studentLname; studentId = stuId; gpa = studentGpa; } public double getGpa() { return gpa; } public String getStudentId() { return studentId; } public String getName() { return lname + ", " + fname; } public void setGpa(double gpaReplacement) { if (gpaReplacement >= 0.0 && gpaReplacement <= 4.0) gpa = gpaReplacement; else System.out.println("Invalid GPA! Please try again."); System.exit(0); } } Now I need to create a toString() method that returns a String formatted something like this: Name: Wilson, Mary Ann ID number: 12345 GPA: 3.5

    Read the article

  • How do I resize a flat vector icon so that it preserves hard edges in Photoshop (CS4)

    - by Adam Singer
    I recently purchased Drew Wilson's Pictos icon library. It is a library of flat, monochromatic icons for use on the web and elsewhere. The only issue is: they're vectors. I know my way around Illustrator a little bit, but ultimately I want to import these icons into Photoshop and resize to various dimensions. The problem I'm having: when I import an icon and resize it to, say, 20x20 pixels, I notice that there is a fair bit of aliasing around the edges of the icon. I'm sure there is some magic number where the edges of these icons will remain crisp, but I can't find any option or setting that will allow me to size these icons properly. Is there a way in Photoshop to snap these icons to the closest size that removes or minimizes the aliasing?

    Read the article

  • Content Box is a Little Off in IE9 ... How to Fix?

    - by Kelsey Nealon
    Hi there! I have a website at www.thetotempole.ca and when viewed in IE9... My websites content box (The green wooden backgrounded box with content inside) is moved slightly over to the left making a space between the actual container and the content box... Is there anyway I can fix this without harming any of the other browsers? Thanks! Screenshot: HTML: <!DOCTYPE html> <head> <title>The Totem Pole News - Movies</title> <!-- Start WOWSlider.com HEAD section --> <link rel="stylesheet" type="text/css" href="engine1/style.css" /> <script type="text/javascript" src="engine1/jquery.js"></script> <!-- End WOWSlider.com HEAD section --> <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setAccount', 'UA-45342007-1']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); </script> <meta charset="utf-8"> <meta name="description" content="A totem pole themed news website posting articles on news, music, movies, video games, and health."> <link href="thecss2.css" rel="stylesheet" type="text/css"> <link rel="icon" type="image/ico" href="images/favicon.ico"> <meta http-equiv="X-UA-Compatible" content="IE=8" /> </head> <body> <div id="container"> <div id="contentbox" align="Center"> <a href="index.html"><div id="banner" align="Center"> </div></a> <div id="navbar"> <p><a href="index.html"><img src="images/home.png" width="65" height="54" alt="picture of a house to relate to the home page (content)" style="position: absolute; left: 23px; top: 16px; width: 57px; height: 48px;"><span style="position: absolute; left: 24px; z-index:2; top: 71px; height: 23px;">Content</span></a> <a href="#"><img src="images/eagleicon.gif" width="73" height="39" alt="An Eagle icon for the News section of the Totem Pole" style="position: absolute; left: 111px; top: 28px;"><span style="position: absolute; z-index: 2; left: 127px; top: 72px;">News</span></a> <a href="#"><img src="images/owlicon.gif" width="81" height="61" alt="An Owl icon for the Music section of the totem pole" style="position: absolute; left: 210px; top: 11px;"><span style="position: absolute; z-index:2; left: 226px; top: 73px;"><strong>Music</strong></span></a><a href="movies.html"><img src="images/wolficon.gif" width="88" height="54" alt="A Wolf icon for the Movies section of the totem pole" style="position: absolute; left: 320px; top: 15px;"><span style="position: absolute; left: 336px; top: 72px; z-index:2;"><strong>Movies</strong></span></a> <a href="#"><img src="images/hareimage.gif" width="60" height="56" alt="A Hare icon for Video Game section of the Totem Pole" style="position: absolute; left: 441px; top: 13px;"><span style="position: absolute; z-index:2; left: 428px; top: 73px;"><strong>Video Games</strong></span></a> <a href="#"><img src="images/bearicon.gif" width="91" height="57" alt="A bear icon for the Health section of The Totem Pole" style="position: absolute; left: 551px; top: 13px;"><span style="position: absolute; left: 580px; top: 72px; z-index:2;">Health</span></a></p> </div> <!--Nav Bar 2--> <div id="navbar2"> <a href="#">About Us</a> <a href="#">Feedback</a> <a href="#">Subscribe</a> </div> <!-- Atomz HTML for Search --> <div id="searchbar"> <form method="get" action="http://search.atomz.com/search/"> <input id="searchbox" size="13" name="sp_q" value="Search..." onFocus="if (this.value == 'Search...') {this.value=''}"> <input class="css_btn_class" type="submit" value="Search"> <input type="hidden" name="sp_a" value="sp1005092e"> <input type="hidden" name="sp_p" value="all"> <input type="hidden" name="sp_f" value="UTF-8"> </form> </div> <!-- Start WOWSlider.com BODY section --> <div id="mywowslider"> <div id="wowslider-container1"> <div class="ws_images"> <ul> <li><img src="images/anchor.jpg" alt="Ron Burgundy" title="Ron Burgundy" id="wows1_0"/>Played by Will Ferrell</li> <li><img src="images/anchor2.jpg" alt="Brian Fantana" title="Brian Fantana" id="wows1_1"/>Played by Paul Rudd</li> <li><img src="images/anchor3.jpg" alt="Brick Tamland" title="Brick Tamland" id="wows1_2"/>Played by Steve Carrell</li> <li><img src="images/anchor4.jpg" alt="Champ Kind" title="Champ Kind" id="wows1_3"/>Played by David Koechner</li> </ul> </div> <div class="ws_bullets"><div> <a href="#" title="Ron Burgundy"><img src="images/anchor.jpg" alt="Ron Burgundy"/>1</a> <a href="#" title="Brian Fantana"><img src="images/anchor2.jpg" alt="Brian Fantana"/>2</a> <a href="#" title="Brick Tamland"><img src="images/anchor3.jpg" alt="Brick Tamland"/>3</a> <a href="#" title="Champ Kind"><img src="images/anchor4.jpg" alt="Champ Kind"/>4</a> </div> </div> <span class="wsl"><a href="http://wowslider.com"></a></span> <div class="ws_shadow"></div> </div> <script type="text/javascript" src="engine1/wowslider.js"></script> <script type="text/javascript" src="engine1/script.js"></script> </div> <!-- End WOWSlider.com BODY section --> <!-- AddThis Smart Layers BEGIN --> <!-- Go to http://www.addthis.com/get/smart-layers to customize --> <script type="text/javascript" src="//s7.addthis.com/js/300/addthis_widget.js#pubid=ra-5279b96309e7df24"></script> <script type="text/javascript"> addthis.layers({ 'theme' : 'transparent', 'share' : { 'position' : 'left', 'numPreferredServices' : 5 } }); </script> <!-- AddThis Smart Layers END --> <div id="sources"><p> Source(s): <a href="http://en.wikipedia.org/wiki/Anchorman_2:_The_Legend_Continues">wikipedia.com</a></p></div> <div id="infocontent"> <p align="left"><em><strong> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Anchorman 2: The Legend Continues</strong></em> is an upcoming American comedy film being released on December 20, 2013, also a sequel to the 2004 film <em>Anchorman: The Legend of Ron Burgandy</em>. On March 28, 2012, actor Will Ferrell officially announced the sequel dressed in character as Ron Burgundy on the late-night talk-show <em>Conan</em>. As with the original film, it is directed by Adam McKay, produced by Judd Apatow, stars Will Ferrell and is written by Adam McKay and Will Ferrell. Unlike the original film, which was distributed by DreamWorks Pictures, <em>The Legend Continues</em> will be distributed by Paramount Pictures.</p> <p align="left"><em><strong>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</strong></em>The movie now has a website at <a href="www.anchormanmovie.com">www.anchormanmovie.com</a> where a countdown for the release of this film can be seen. By the looks of these images, I think we can expect big things when the movie comes out this December. Enjoy the poster photos and trailers all posted below, and don't forget to submit your vote in the poll!</p> </div> <div id="trailer1"><iframe width="560" height="315" src="//www.youtube.com/embed/Elczv0ghqw0?rel=0" frameborder="0" allowfullscreen></iframe></div> <div id="trailer2"> <iframe width="560" height="315" src="//www.youtube.com/embed/mZ-JX-7B3uM?rel=0" frameborder="0" allowfullscreen></iframe> </div> <div id="poll"> <form method="post" action="http://poll.pollcode.com/763294"><table style="border: black 1px solid;" border="1" width="175" bgcolor="EEEEEE" cellspacing="2" cellpadding="0"><tr><td colspan="2" height="10"><font face="Verdana" size="2" color="000000"><b>What Rating Do You Think This Will Recieve</b></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="1" id="763294answer1"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer1">10</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="2" id="763294answer2"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer2">9</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="3" id="763294answer3"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer3">8</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="4" id="763294answer4"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer4">7</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="5" id="763294answer5"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer5">6</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="6" id="763294answer6"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer6">5</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="7" id="763294answer7"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer7">4</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="8" id="763294answer8"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer8">3</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="9" id="763294answer9"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer9">2</label></font></td></tr><tr><td width="5"><input type="radio" name="answer" value="10" id="763294answer10"></td><td>&nbsp;<font face="Verdana" size="2" color="000000"><label for="763294answer10">1</label></font></td></tr><tr><td colspan="2" height="10"><center><input type="submit" value=" Vote ">&nbsp;&nbsp;<input title="Clicking this will send you to a new page" type="submit" name="view" value=" View "></center></td></tr><tr><td colspan="2" align="right"><font face="Verdana" height="5" size="1" color="000000"></font></td></tr></table></form></div> <span style="position: absolute; left: 0px; top: 225px; width: 1000px; border-bottom: 2px black double; height: 58px;"> <h1 style="font-weight: normal; font-size:28px"><em>Anchorman 2 Arrives Soon</em></h1></span> <div id="contentbox2"></div> <!--Footer Div --> <center><div id="footer"><a href="#">Sitemap</a> <a href="#">About Us</a> <a href="#">Feedback</a></div></center> <div id="disqus"><div id="disqus_thread"></div> <script type="text/javascript"> /* * * CONFIGURATION VARIABLES: EDIT BEFORE PASTING INTO YOUR WEBPAGE * * */ var disqus_shortname = 'thetotempoleanchorman2'; // required: replace example with your forum shortname /* * * DON'T EDIT BELOW THIS LINE * * */ (function() { var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true; dsq.src = '//' + disqus_shortname + '.disqus.com/embed.js'; (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq); })(); </script> <noscript>Please enable JavaScript to view the <a href="http://disqus.com/?ref_noscript">comments powered by Disqus.</a></noscript> <a href="http://disqus.com" class="dsq-brlink">comments powered by <span class="logo-disqus">Disqus</span></a></div> <!-- This is the end of the contentbox --></div> <!-- This is the end of the container div --> </div> </body> </html> CSS: html { background: url(images/pine.jpg) no-repeat center center fixed; -webkit-background-size: cover; -moz-background-size: cover; -o-background-size: cover; background-size: cover; filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='images/pine.jpg', sizingMethod='scale'); -ms-filter: "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='images/pine.jpg', sizingMethod='scale')"; } body { margin-bottom:0px; font-family: Verdana, Geneva, sans-serif; } a { outline : none; border: none; } a:hover { color: #0FC; } #container { width: 1000px; height:1924px; position:relative; margin-right: auto; margin-left: auto; z-index:1; margin-bottom: 50px; } #facebook { position:fixed; right:100px; z-index:15; } #twitter { position:fixed; z-index:16; right:120px; } #google { position:fixed; top:7px; right: 135px; } #socialmediaplugins { text-align: right; position: fixed; background: rgb(125,126,125); /* Old browsers */ background: -moz-linear-gradient(top, rgba(125,126,125,1) 0%, rgba(247,247,247,1) 100%); /* FF3.6+ */ background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(125,126,125,1)), color-stop(100%,rgba(247,247,247,1))); /* Chrome,Safari4+ */ background: -webkit-linear-gradient(top, rgba(125,126,125,1) 0%,rgba(247,247,247,1) 100%); /* Chrome10+,Safari5.1+ */ background: -o-linear-gradient(top, rgba(125,126,125,1) 0%,rgba(247,247,247,1) 100%); /* Opera 11.10+ */ background: -ms-linear-gradient(top, rgba(125,126,125,1) 0%,rgba(247,247,247,1) 100%); /* IE10+ */ background: linear-gradient(to bottom, rgba(125,126,125,1) 0%,rgba(247,247,247,1) 100%); /* W3C */ filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#7d7e7d', endColorstr='#f7f7f7',GradientType=0 ); /* IE6-9 */ margin: 0px; top: 0px; left: 0px; right: 0px; z-index:14; } #searchbox { background-color:#01bff6; border-radius:4px; } #searchbox:hover { background-color:#76b618; border-radius:4px; } #searchbox:active { background-color:#01bff6; border-radius:4px; } #contentbox { background-color:black; background-image:url(images/wooden.jpg); width: 1000px; margin-bottom:50px; height: 1924px; box-shadow:2px 2px 10px 10px #060606; -webkit-box-shadow:2px 2px 10px 10px #060606; -moz-box-shadow:2px 2px 10px 10px #060606; /* For IE<9 */ filter: progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=0,strength=5), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=45,strength=2), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=90,strength=5), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=135,strength=5), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=180,strength=10), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=225,strength=5), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=270,strength=5), progid:DXImageTransform.Microsoft.Shadow(color=#060606,direction=315,strength=2); } #contentbox2 { background-image:url(images/woodenmovies.jpg); top:299px; width: 1000px; margin-bottom:50px; height: 1625px; position: absolute; } #banner { background-image:url(images/totempolebanner.gif); position:absolute; top:25px; width:768px; height:120px; left:116px; } #navbar { float: left; position: absolute; top: 146px; left: 76px; width: 844px; height: 158px; font-weight:bold; } #navbar a { color:#0C6; font-size: 13px; } #navbar a:hover { color:#0F9; font-size: 13px; } #navbar2 a:hover { color:#0F9; } #navbar2 a{ text-decoration:none; color:#0C6; } #navbar2 { position: absolute; top: 4px; left: 766px; width: 273px; height: 24px; font-size: 11px; } #searchbar { position: absolute; top: 23px; left: 885px; width: 118px; height: 69px; } .css_btn_class { font-size:9px; position: relative; top:0px; right:4px; width:90px; height:25px; font-family:Verdana; font-weight:normal; -moz-border-radius:7px; -webkit-border-radius:7px; border-radius:7px; border:1px solid #35d914; padding:7px 24px; text-decoration:none; background:-webkit-gradient( linear, left top, left bottom, color-stop(5%, #ff9d00), color-stop(100%, #ffe711) ); background:-moz-linear-gradient( center top, #ff9d00 5%, #ffe711 100% ); background:-ms-linear-gradient( top, #ff9d00 5%, #ffe711 100% ); background-color:#ff9d00; color:#ff0000; display:inline-block; text-shadow:0px 0px 1px #117cff; -webkit-box-shadow: 0px 0px 0px 0px #117cff; -moz-box-shadow: 0px 0px 0px 0px #117cff; box-shadow: 0px 0px 0px 0px #117cff; background-image: url(images/unnamed.gif); background-repeat:no-repeat; background-position:right; }.css_btn_class:hover { width:90px; background:-webkit-gradient( linear, left top, left bottom, color-stop(5%, #ffe711), color-stop(100%, #ff9d00) ); background:-moz-linear-gradient( center top, #ffe711 5%, #ff9d00 100% ); background:-ms-linear-gradient( top, #ffe711 5%, #ff9d00 100% ); background-color:#ffe711; background-image: url(images/unnamed.gif); background-repeat:no-repeat; background-position:right; }.css_btn_class:active { position:relative; width:90px; top:1px; background-image: url(images/unnamed.gif); background-repeat:no-repeat; background-position:right; } /* This css button was generated by css-button-generator.com */ img {border:none;} #eagle { position:relative; right: 144px; top:299px; } #owl { top:624px; position:absolute; left:0px; } #wolf { top:949px; position:absolute; right:0px; } #hare { top:1274px; position:absolute; left:0px; } #bear { top:1599px; position:absolute; right:0px; } #footer { position: absolute; left: 393px; top: 1941px; width: 251px; color: #0F9; } #footer a { color: #0f9; } .atss { left: 0; } #infocontent { position: absolute; z-index: 3; left: 15px; top: 333px; height: 348px; width: 789px; } #mywowslider { position: absolute; z-index: 3; left: 640px; top: 684px; } #poll { position: absolute; z-index: 3; left: 815px; top: 344px; } #trailer1 { position: absolute; z-index: 3; left: 40px; top: 598px; } #trailer2 { position: absolute; z-index: 3; left: 40px; top: 948px; } #trailer1header { position: absolute; z-index: 3; left: 200px; top: 550px; width: 240px; font-style: italic; font-weight: normal; } #trailer2header { position: absolute; z-index: 3; left: 200px; top: 898px; width: 241px; height: 51px; font-style: italic; font-weight: normal; } #disqus { position: absolute; z-index: 3; left: 0px; top: 1340px; } #sources { position: absolute; z-index: 3; left: 394px; top: 1249px; width: 212px; }

    Read the article

  • Best Practices for Building a Virtualized SPARC Computing Environment

    - by Scott Elvington
    Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Oracle just published Best Practices for Building a Virtualized SPARC Computing Environment, a white paper that provides guidance on the complete hardware and software stack for deploying and managing your physical and virtual SPARC infrastructure. The solution is based on Oracle SPARC T4 servers, Oracle Solaris 11 with Oracle VM for SPARC 2.2, Sun ZFS storage appliances, Sun 10GbE 72 port switches and Oracle Enterprise Manager Ops Center 12c. The paper emphasizes the value and importance of planning the resources (compute, network and storage) that will comprise the virtualized environment to achieve the desired capacity, performance and availability characteristics. The document also details numerous operational best practices that will help you deliver on those characteristics with unique capabilities provided by Enterprise Manager Ops Center including policy-based guest placement, pool resource balancing and automated guest recovery in the event of server failure. Plenty of references to supplementary documentation are included to help point you to additional resources. Whether you’re building the first stages of your private cloud or a general-purpose virtualized SPARC computing environment, these documented best practices will help ensure success. Please join Phil Bullinger and Steve Wilson from Oracle to learn more about breakthrough efficiency in private cloud infrastructure and how SPARC based virtualization can help you get started on your cloud journey. Stay Connected: Twitter |  Face book |  You Tube |  Linked in |  Newsletter

    Read the article

  • Silverlight Cream for May 17, 2010 -- #863

    - by Dave Campbell
    In this Issue: Christian Schormann, Vladimir Bodurov, Pete Brown, Justin Angel, John Papa(-2-), Fons Sonnemans, Miroslav Miroslavov, and Jeremy Likness. Shoutouts: Jeff Brand has been doing WP7 presentations and posted Windows Phone 7 Presentation and Sample Code Mark Tucker posted about his Windows Phone 7 Presentation at Desert Code Camp 2010 John Allwright discusses 4 New case Studies on Silverlight at the Winter Olympics From SilverlightCream.com: New Video by Jon Harris: Blend 4 for Windows Phone in 90 Seconds Christian Schormann is discussing a second 90-second Expression Blend video tutorial by Jon Harris... this second one is about Blend 4 for WP7. XmlCodeEditor – Silverlight 4 control for editing XML and HTML on the browser Vladimir Bodurov has a post up extending the RichTextBox control to add coloring for HTML and XAML ... it colors as you type, and he plans on adding Intellisense! Creating a Simple Report Writer in Silverlight 4 While working on his book, Pete Brown decided to share some Silverlight 'Report Writer' work with us... check out that list of goals near the top that are all met... looks great to me! Windows Phone 7 - Unlocked ROMs Justin Angel has a good long post about a subject I've stayed away from until now that someone of Justin's level of knowledge has approached it: WP7 ROMs. Silverlight 4 Tools for Visual Studio 2010 Launch: New Designer Capabilities (Silverlight TV 27) John Papa has Silverlight TV 27 up today and is talking about the Silverlight 4 Tools for VS2010 launch with Mark Wilson-Thomas ... the video would be a great place to pick up some of the new features (hint, hint) WCF RIA Services v1.0 Launch! (Silverlight TV 28) John Papa also has Silverlight TV 28 up, talking with Nikhil Kothari and Dinesh Kulkarni about the v 1.0 release of WCF RIA Services. RightMouseTrigger Fons Sonnemans updated his MineSweeper game and has it posted at Silver Arcade, this version supports right mouse click via RightMouseTrigger code that he is sharing. Smoke effect The 'Smoke Effect' menus at the CompleteIT site are awesome, and this time out, Miroslav Miroslavov discusses how that was done and gives up the code...! WebClient and DeploymentCatalog gotchas in Silverlight OOB Jeremy Likness has a post up to give you some relief if you hit the same MEF/Silverlight gotcha he did when running OOB... like not running in OOB for instance. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

    Read the article

  • PTLQueue : a scalable bounded-capacity MPMC queue

    - by Dave
    Title: Fast concurrent MPMC queue -- I've used the following concurrent queue algorithm enough that it warrants a blog entry. I'll sketch out the design of a fast and scalable multiple-producer multiple-consumer (MPSC) concurrent queue called PTLQueue. The queue has bounded capacity and is implemented via a circular array. Bounded capacity can be a useful property if there's a mismatch between producer rates and consumer rates where an unbounded queue might otherwise result in excessive memory consumption by virtue of the container nodes that -- in some queue implementations -- are used to hold values. A bounded-capacity queue can provide flow control between components. Beware, however, that bounded collections can also result in resource deadlock if abused. The put() and take() operators are partial and wait for the collection to become non-full or non-empty, respectively. Put() and take() do not allocate memory, and are not vulnerable to the ABA pathologies. The PTLQueue algorithm can be implemented equally well in C/C++ and Java. Partial operators are often more convenient than total methods. In many use cases if the preconditions aren't met, there's nothing else useful the thread can do, so it may as well wait via a partial method. An exception is in the case of work-stealing queues where a thief might scan a set of queues from which it could potentially steal. Total methods return ASAP with a success-failure indication. (It's tempting to describe a queue or API as blocking or non-blocking instead of partial or total, but non-blocking is already an overloaded concurrency term. Perhaps waiting/non-waiting or patient/impatient might be better terms). It's also trivial to construct partial operators by busy-waiting via total operators, but such constructs may be less efficient than an operator explicitly and intentionally designed to wait. A PTLQueue instance contains an array of slots, where each slot has volatile Turn and MailBox fields. The array has power-of-two length allowing mod/div operations to be replaced by masking. We assume sensible padding and alignment to reduce the impact of false sharing. (On x86 I recommend 128-byte alignment and padding because of the adjacent-sector prefetch facility). Each queue also has PutCursor and TakeCursor cursor variables, each of which should be sequestered as the sole occupant of a cache line or sector. You can opt to use 64-bit integers if concerned about wrap-around aliasing in the cursor variables. Put(null) is considered illegal, but the caller or implementation can easily check for and convert null to a distinguished non-null proxy value if null happens to be a value you'd like to pass. Take() will accordingly convert the proxy value back to null. An advantage of PTLQueue is that you can use atomic fetch-and-increment for the partial methods. We initialize each slot at index I with (Turn=I, MailBox=null). Both cursors are initially 0. All shared variables are considered "volatile" and atomics such as CAS and AtomicFetchAndIncrement are presumed to have bidirectional fence semantics. Finally T is the templated type. I've sketched out a total tryTake() method below that allows the caller to poll the queue. tryPut() has an analogous construction. Zebra stripping : alternating row colors for nice-looking code listings. See also google code "prettify" : https://code.google.com/p/google-code-prettify/ Prettify is a javascript module that yields the HTML/CSS/JS equivalent of pretty-print. -- pre:nth-child(odd) { background-color:#ff0000; } pre:nth-child(even) { background-color:#0000ff; } border-left: 11px solid #ccc; margin: 1.7em 0 1.7em 0.3em; background-color:#BFB; font-size:12px; line-height:65%; " // PTLQueue : Put(v) : // producer : partial method - waits as necessary assert v != null assert Mask = 1 && (Mask & (Mask+1)) == 0 // Document invariants // doorway step // Obtain a sequence number -- ticket // As a practical concern the ticket value is temporally unique // The ticket also identifies and selects a slot auto tkt = AtomicFetchIncrement (&PutCursor, 1) slot * s = &Slots[tkt & Mask] // waiting phase : // wait for slot's generation to match the tkt value assigned to this put() invocation. // The "generation" is implicitly encoded as the upper bits in the cursor // above those used to specify the index : tkt div (Mask+1) // The generation serves as an epoch number to identify a cohort of threads // accessing disjoint slots while s-Turn != tkt : Pause assert s-MailBox == null s-MailBox = v // deposit and pass message Take() : // consumer : partial method - waits as necessary auto tkt = AtomicFetchIncrement (&TakeCursor,1) slot * s = &Slots[tkt & Mask] // 2-stage waiting : // First wait for turn for our generation // Acquire exclusive "take" access to slot's MailBox field // Then wait for the slot to become occupied while s-Turn != tkt : Pause // Concurrency in this section of code is now reduced to just 1 producer thread // vs 1 consumer thread. // For a given queue and slot, there will be most one Take() operation running // in this section. // Consumer waits for producer to arrive and make slot non-empty // Extract message; clear mailbox; advance Turn indicator // We have an obvious happens-before relation : // Put(m) happens-before corresponding Take() that returns that same "m" for T v = s-MailBox if v != null : s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 // unlock slot to admit next producer and consumer return v Pause tryTake() : // total method - returns ASAP with failure indication for auto tkt = TakeCursor slot * s = &Slots[tkt & Mask] if s-Turn != tkt : return null T v = s-MailBox // presumptive return value if v == null : return null // ratify tkt and v values and commit by advancing cursor if CAS (&TakeCursor, tkt, tkt+1) != tkt : continue s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 return v The basic idea derives from the Partitioned Ticket Lock "PTL" (US20120240126-A1) and the MultiLane Concurrent Bag (US8689237). The latter is essentially a circular ring-buffer where the elements themselves are queues or concurrent collections. You can think of the PTLQueue as a partitioned ticket lock "PTL" augmented to pass values from lock to unlock via the slots. Alternatively, you could conceptualize of PTLQueue as a degenerate MultiLane bag where each slot or "lane" consists of a simple single-word MailBox instead of a general queue. Each lane in PTLQueue also has a private Turn field which acts like the Turn (Grant) variables found in PTL. Turn enforces strict FIFO ordering and restricts concurrency on the slot mailbox field to at most one simultaneous put() and take() operation. PTL uses a single "ticket" variable and per-slot Turn (grant) fields while MultiLane has distinct PutCursor and TakeCursor cursors and abstract per-slot sub-queues. Both PTL and MultiLane advance their cursor and ticket variables with atomic fetch-and-increment. PTLQueue borrows from both PTL and MultiLane and has distinct put and take cursors and per-slot Turn fields. Instead of a per-slot queues, PTLQueue uses a simple single-word MailBox field. PutCursor and TakeCursor act like a pair of ticket locks, conferring "put" and "take" access to a given slot. PutCursor, for instance, assigns an incoming put() request to a slot and serves as a PTL "Ticket" to acquire "put" permission to that slot's MailBox field. To better explain the operation of PTLQueue we deconstruct the operation of put() and take() as follows. Put() first increments PutCursor obtaining a new unique ticket. That ticket value also identifies a slot. Put() next waits for that slot's Turn field to match that ticket value. This is tantamount to using a PTL to acquire "put" permission on the slot's MailBox field. Finally, having obtained exclusive "put" permission on the slot, put() stores the message value into the slot's MailBox. Take() similarly advances TakeCursor, identifying a slot, and then acquires and secures "take" permission on a slot by waiting for Turn. Take() then waits for the slot's MailBox to become non-empty, extracts the message, and clears MailBox. Finally, take() advances the slot's Turn field, which releases both "put" and "take" access to the slot's MailBox. Note the asymmetry : put() acquires "put" access to the slot, but take() releases that lock. At any given time, for a given slot in a PTLQueue, at most one thread has "put" access and at most one thread has "take" access. This restricts concurrency from general MPMC to 1-vs-1. We have 2 ticket locks -- one for put() and one for take() -- each with its own "ticket" variable in the form of the corresponding cursor, but they share a single "Grant" egress variable in the form of the slot's Turn variable. Advancing the PutCursor, for instance, serves two purposes. First, we obtain a unique ticket which identifies a slot. Second, incrementing the cursor is the doorway protocol step to acquire the per-slot mutual exclusion "put" lock. The cursors and operations to increment those cursors serve double-duty : slot-selection and ticket assignment for locking the slot's MailBox field. At any given time a slot MailBox field can be in one of the following states: empty with no pending operations -- neutral state; empty with one or more waiting take() operations pending -- deficit; occupied with no pending operations; occupied with one or more waiting put() operations -- surplus; empty with a pending put() or pending put() and take() operations -- transitional; or occupied with a pending take() or pending put() and take() operations -- transitional. The partial put() and take() operators can be implemented with an atomic fetch-and-increment operation, which may confer a performance advantage over a CAS-based loop. In addition we have independent PutCursor and TakeCursor cursors. Critically, a put() operation modifies PutCursor but does not access the TakeCursor and a take() operation modifies the TakeCursor cursor but does not access the PutCursor. This acts to reduce coherence traffic relative to some other queue designs. It's worth noting that slow threads or obstruction in one slot (or "lane") does not impede or obstruct operations in other slots -- this gives us some degree of obstruction isolation. PTLQueue is not lock-free, however. The implementation above is expressed with polite busy-waiting (Pause) but it's trivial to implement per-slot parking and unparking to deschedule waiting threads. It's also easy to convert the queue to a more general deque by replacing the PutCursor and TakeCursor cursors with Left/Front and Right/Back cursors that can move either direction. Specifically, to push and pop from the "left" side of the deque we would decrement and increment the Left cursor, respectively, and to push and pop from the "right" side of the deque we would increment and decrement the Right cursor, respectively. We used a variation of PTLQueue for message passing in our recent OPODIS 2013 paper. ul { list-style:none; padding-left:0; padding:0; margin:0; margin-left:0; } ul#myTagID { padding: 0px; margin: 0px; list-style:none; margin-left:0;} -- -- There's quite a bit of related literature in this area. I'll call out a few relevant references: Wilson's NYU Courant Institute UltraComputer dissertation from 1988 is classic and the canonical starting point : Operating System Data Structures for Shared-Memory MIMD Machines with Fetch-and-Add. Regarding provenance and priority, I think PTLQueue or queues effectively equivalent to PTLQueue have been independently rediscovered a number of times. See CB-Queue and BNPBV, below, for instance. But Wilson's dissertation anticipates the basic idea and seems to predate all the others. Gottlieb et al : Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors Orozco et al : CB-Queue in Toward high-throughput algorithms on many-core architectures which appeared in TACO 2012. Meneghin et al : BNPVB family in Performance evaluation of inter-thread communication mechanisms on multicore/multithreaded architecture Dmitry Vyukov : bounded MPMC queue (highly recommended) Alex Otenko : US8607249 (highly related). John Mellor-Crummey : Concurrent queues: Practical fetch-and-phi algorithms. Technical Report 229, Department of Computer Science, University of Rochester Thomasson : FIFO Distributed Bakery Algorithm (very similar to PTLQueue). Scott and Scherer : Dual Data Structures I'll propose an optimization left as an exercise for the reader. Say we wanted to reduce memory usage by eliminating inter-slot padding. Such padding is usually "dark" memory and otherwise unused and wasted. But eliminating the padding leaves us at risk of increased false sharing. Furthermore lets say it was usually the case that the PutCursor and TakeCursor were numerically close to each other. (That's true in some use cases). We might still reduce false sharing by incrementing the cursors by some value other than 1 that is not trivially small and is coprime with the number of slots. Alternatively, we might increment the cursor by one and mask as usual, resulting in a logical index. We then use that logical index value to index into a permutation table, yielding an effective index for use in the slot array. The permutation table would be constructed so that nearby logical indices would map to more distant effective indices. (Open question: what should that permutation look like? Possibly some perversion of a Gray code or De Bruijn sequence might be suitable). As an aside, say we need to busy-wait for some condition as follows : "while C == 0 : Pause". Lets say that C is usually non-zero, so we typically don't wait. But when C happens to be 0 we'll have to spin for some period, possibly brief. We can arrange for the code to be more machine-friendly with respect to the branch predictors by transforming the loop into : "if C == 0 : for { Pause; if C != 0 : break; }". Critically, we want to restructure the loop so there's one branch that controls entry and another that controls loop exit. A concern is that your compiler or JIT might be clever enough to transform this back to "while C == 0 : Pause". You can sometimes avoid this by inserting a call to a some type of very cheap "opaque" method that the compiler can't elide or reorder. On Solaris, for instance, you could use :"if C == 0 : { gethrtime(); for { Pause; if C != 0 : break; }}". It's worth noting the obvious duality between locks and queues. If you have strict FIFO lock implementation with local spinning and succession by direct handoff such as MCS or CLH,then you can usually transform that lock into a queue. Hidden commentary and annotations - invisible : * And of course there's a well-known duality between queues and locks, but I'll leave that topic for another blog post. * Compare and contrast : PTLQ vs PTL and MultiLane * Equivalent : Turn; seq; sequence; pos; position; ticket * Put = Lock; Deposit Take = identify and reserve slot; wait; extract & clear; unlock * conceptualize : Distinct PutLock and TakeLock implemented as ticket lock or PTL Distinct arrival cursors but share per-slot "Turn" variable provides exclusive role-based access to slot's mailbox field put() acquires exclusive access to a slot for purposes of "deposit" assigns slot round-robin and then acquires deposit access rights/perms to that slot take() acquires exclusive access to slot for purposes of "withdrawal" assigns slot round-robin and then acquires withdrawal access rights/perms to that slot At any given time, only one thread can have withdrawal access to a slot at any given time, only one thread can have deposit access to a slot Permissible for T1 to have deposit access and T2 to simultaneously have withdrawal access * round-robin for the purposes of; role-based; access mode; access role mailslot; mailbox; allocate/assign/identify slot rights; permission; license; access permission; * PTL/Ticket hybrid Asymmetric usage ; owner oblivious lock-unlock pairing K-exclusion add Grant cursor pass message m from lock to unlock via Slots[] array Cursor performs 2 functions : + PTL ticket + Assigns request to slot in round-robin fashion Deconstruct protocol : explication put() : allocate slot in round-robin fashion acquire PTL for "put" access store message into slot associated with PTL index take() : Acquire PTL for "take" access // doorway step seq = fetchAdd (&Grant, 1) s = &Slots[seq & Mask] // waiting phase while s-Turn != seq : pause Extract : wait for s-mailbox to be full v = s-mailbox s-mailbox = null Release PTL for both "put" and "take" access s-Turn = seq + Mask + 1 * Slot round-robin assignment and lock "doorway" protocol leverage the same cursor and FetchAdd operation on that cursor FetchAdd (&Cursor,1) + round-robin slot assignment and dispersal + PTL/ticket lock "doorway" step waiting phase is via "Turn" field in slot * PTLQueue uses 2 cursors -- put and take. Acquire "put" access to slot via PTL-like lock Acquire "take" access to slot via PTL-like lock 2 locks : put and take -- at most one thread can access slot's mailbox Both locks use same "turn" field Like multilane : 2 cursors : put and take slot is simple 1-capacity mailbox instead of queue Borrow per-slot turn/grant from PTL Provides strict FIFO Lock slot : put-vs-put take-vs-take at most one put accesses slot at any one time at most one put accesses take at any one time reduction to 1-vs-1 instead of N-vs-M concurrency Per slot locks for put/take Release put/take by advancing turn * is instrumental in ... * P-V Semaphore vs lock vs K-exclusion * See also : FastQueues-excerpt.java dice-etc/queue-mpmc-bounded-blocking-circular-xadd/ * PTLQueue is the same as PTLQB - identical * Expedient return; ASAP; prompt; immediately * Lamport's Bakery algorithm : doorway step then waiting phase Threads arriving at doorway obtain a unique ticket number Threads enter in ticket order * In the terminology of Reed and Kanodia a ticket lock corresponds to the busy-wait implementation of a semaphore using an eventcount and a sequencer It can also be thought of as an optimization of Lamport's bakery lock was designed for fault-tolerance rather than performance Instead of spinning on the release counter, processors using a bakery lock repeatedly examine the tickets of their peers --

    Read the article

< Previous Page | 52 53 54 55 56 57 58 59 60 61 62 63  | Next Page >