Search Results

Search found 20211 results on 809 pages for 'language implementation'.

Page 705/809 | < Previous Page | 701 702 703 704 705 706 707 708 709 710 711 712  | Next Page >

• Is `super` local variable?

  - by Michael

  // A : Parent @implementation A -(id) init { // change self here then return it } @end A A *a = [[A alloc] init]; a. Just wondering, if self is a local variable or global? If it's local then what is the point of self = [super init] in init? I can successfully define some local variable and use like this, why would I need to assign it to self. -(id) init { id tmp = [super init]; if(tmp != nil) { //do stuff } return tmp; } b. If [super init] returns some other object instance and I have to overwrite self then I will not be able to access A's methods any more, since it will be completely new object? Am I right? c. super and self pointing to the same memory and the major difference between them is method lookup order. Am I right? sorry, don't have Mac to try, learning theory as for now...

  Read the article

• Custom stream wrappers, what could they be useful for in web applications?

  - by michael

  I suppose the concept is language agnostic, but I don't know what it's called in other languages. In PHP they're Stream Wrappers. In short, a wrapper class that allows manipulation of a streamable resource (resource that can be read to/written to/seek into, such as a file, a db, an url). For example, in a template engine (a view), upon including a template file such as: include "view.wrapper://path/to/my/template/file.phtml"; my custom wrapper, declared elsewhere and associated with "view.wrapper", would first intercepts the file to replace such things as short tags (<?=) with a more verbose counterpart (<?php echo). This allows developers to use short tags in views, even if the server isn't set to allow it. It can also be applied to the preprocessing of views pseudo syntax such as {@myVar} (e.g. replacing it with $this->myVar). This is only one application of custom stream wrappers, but the feature seems powerful enough to make me think that there are others that could make life a lot simpler for developers. What have you built, or thought about building, custom stream wrappers for? where have you seen some interesting implementations? I'm particularly interested in their applications in web development.

  Read the article

• Why do I have memory problems?

  - by Tattat

  I got this error from XCode: objc[8422]: FREED(id): message release sent to freed object=0x3b120c0 I googled and find that is related to the memory. But I don't know which line of code I go wrong, any ideas? After I launch my app in simulator, it prompts a second, than, no other error except the error above. @implementation MyAppDelegate @synthesize window; @synthesize viewController; - (void)applicationDidFinishLaunching:(UIApplication *)application { // Override point for customization after app launch [window addSubview:viewController.view]; [window makeKeyAndVisible]; [self changeScene:[MainGameMenuScene class]]; } - (void)dealloc { [viewController release]; [window release]; [super dealloc]; } - (void) changeScene: (Class) scene { BOOL animateTransition = true; if(animateTransition){ [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:0.5]; [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:window cache:YES]; //does nothing without this line. } if( viewController.view != nil ) { [viewController.view removeFromSuperview]; //remove view from window's subviews. [viewController.view release]; //release gamestate } viewController.view = [[scene alloc] initWithFrame:CGRectMake(0, 0, IPHONE_WIDTH, IPHONE_HEIGHT) andManager:self]; //now set our view as visible [window addSubview:viewController.view]; [window makeKeyAndVisible]; if(animateTransition){ [UIView commitAnimations]; } }

  Read the article

• getting active records to display as a plist

  - by phil swenson

  I'm trying to get a list of active record results to display as a plist for being consumed by the iphone. I'm using the plist gem v 3.0. My model is called Post. And I want Post.all (or any array or Posts) to display correctly as a Plist. I have it working fine for one Post instance: [http://pastie.org/580902][1] that is correct, what I would expect. To get that behavior I had to do this: class Post < ActiveRecord::Base def to_plist attributes.to_plist end end However, when I do a Post.all, I can't get it to display what I want. Here is what happens: http://pastie.org/580909 I get marshalling. I want output more like this: [http://pastie.org/580914][2] I suppose I could just iterate the result set and append the plist strings. But seems ugly, I'm sure there is a more elegant way to do this. I am rusty on Ruby right now, so the elegant way isn't obvious to me. Seems like I should be able to override ActiveRecord and make result-sets that pull back more than one record take the ActiveRecord::Base to_plist and make another to_plist implementation. In rails, this would go in environment.rb, right?

  Read the article

• Redirect after refreshing update panel

  - by teebot.be

  Hello, Do you think it's possible to refresh an update panel and immediately after redirecting the response (for instance a download) ? I tried this: an invisible button - as an asyncpostbacktrigger a download button - when it is clicked the onclientclick clicks the invisible button the click event on the invisible button refreshes the update panel then the download button click event launches the download (normal postback which launches the download) However for some reason when the invisible button is clicked by the download button client script, it doesn't refresh the update panel.. Do you have an idea why it doesn't work? Or do you have other and cleaner techniques? Here's how the elements are declared: <asp:Button runat="server" ID="ButtonInvisible" Text="" Click="RefreshDisplay" /> <asp:Button runat="server" ID="ButtonDownload" Text="Download" OnClientClick="clickInvisible(this.id)" Click="Download" /><Triggers> <asp:AsyncPostBackTrigger ControlID="ButtonInvisible" /></Triggers> //the javascript <script type="text/javascript" language="javascript"> function clickInvisible(idButton) { document.getElementById('ButtonInvisible').click(); }</script> ' //the methods Download(object source, EventArgs e){Response.Redirect("test.txt")} RefreshDisplay(object source, EventArgs e){ ButtonCancel.Enabled = false;}

  Read the article

• Good C string libary

  - by chamakits

  Hello all. I recently got inspired to start up a project I've been wanting to code for a while. I want to do it in C, because memory handling is key this application. I was searching around for a good implementation of strings in C, since I know me doing it myself could lead to some messy buffer overflows, and I expect to be dealing with a fairly big amount of strings. I found this article which gives details on each, but they each seem like they have a good amount of cons going for them (don't get me wrong, this article is EXTREMELY helpful, but it still worries me that even if I were to choose one of those, I wouldn't be using the best I can get). I also don't know how up to date the article is, hence my current plea. What I'm looking for is something that may hold a large amount of characters, and simplifies the process of searching through the string. If it allows me to tokenize the string in any way, even better. Also, it should have some pretty good I/O performance. Printing, and formatted printing isn't quite a top priority. I know I shouldn't expect a library to do all the work for me, but was just wandering if there was a well documented string function out there that could save me some time and some work. Any help is greatly appreciated. Thanks in advance! EDIT: I was asked about the license I prefer. Any sort of open source license will do, but preferably GPL (v2 or v3). EDIt2: I found betterString (bstring) library and it looks pretty good. Good documentation, small yet versatile amount of functions, and easy to mix with c strings. Anyone have any good or bad stories about it? The only downside I've read about it is that it lacks Unicode (again, read about this, haven't seen it face to face just yet), but everything else seems pretty good. EDIT3: Also, preferable that its pure C.

  Read the article

• Sockets and COBOL

  - by kati

  I have received a job at a hospital which still uses COBOL for all organizational work, the whole (now 20 Terabyte) database (Which was a homebrew in, guess what, COBOL) is filled with the data of every patient since the last 45 (or so) years. So that was my story. Now to my question: Currently, all sockets were (from what I've seen) implemented by COBOL programs writing their data into files. These files then were read out by C++ programs (That was an additional module added in the late 1980s) and using C++ sockets sent to the database. Now this solution has stopped working as they are moving the database from COBOL to COBOL, yes - they didn't use MySQL or so - they implemented a new database - again in COBOL. I asked the guy that worked there before me (hes around 70 now) why the hell someone would do that and he told me that he is so good at COBOL that he doesn't want to write it in any other language. So far so good now my question: How can I implement socket connections in COBOL? I need to create an interface to the external COBOL database located at, for example, 192.168.1.23:283.

  Read the article

• guarantee child records either in one table or another, but not both?

  - by user151841

  I have a table with two child tables. For each record in the parent table, I want one and only one record in one of the child tables -- not one in each, not none. How to I define that? Here's the backstory. Feel free to criticize this implementation, but please answer the question above, because this isn't the only time I've encountered it: I have a database that holds data pertaining to user surveys. It was originally designed with one authentication method for starting a survey. Since then, requirements have changed, and now there are two different ways someone could sign on to start a survey. Originally I captured the authentication token in a column in the survey table. Since requirements changed, there are three other bits of data that I want to capture in authentication. So for each record in the survey table, I'm either going to have one token, or a set of three. All four of these are of different types, so my thought was, instead of having four columns where either one is going to be null, or three are going to be null ( or even worse, a bad mashup of either of those scenarios ), I would have two child tables, one for holding the single authentication token, the other for holding the three. Problem is, I don't know offhand how to define that in DDL. I'm using MySQL, so maybe there's a feature that MySQL doesn't implement that lets me do this.

  Read the article

• Should I be backing up a webapp's data to another host continuously ?

  - by user196289

  I have webapp in development. I need to plan for what happens if the host goes down. I will lose some very recent session status (which I can live with) and everything else should be persistently stored in the database. If I am starting up again after an outage, can I expect a good host to reconstruct the database to within minutes of where I was up to ? Or seconds ? Or should I build in a background process to continually mirror the database elsewhere ? What is normal / sensible ? Obviously a good host will have RAID and other redundancy so the likelihood of total loss should be low, and if they have periodic backups I should lose only very recent stuff but this is presumably likely to be designed with almost static web content in mind, and my site is transactional with new data being filed continuously (with a customer expectation that I don't ever lose it). Any suggestions / advice ? Are there off the shelf frameworks for doing this ? (I'm primarily working in Java) And should I just plan to save the data or should I plan to have an alternative usable host implementation ready to launch in case the host doesn't come back up in a suitable timeframe ?

  Read the article

• Array Assignment

  - by Mahesh

  Let me explain with an example - #include <iostream> void foo( int a[2], int b[2] ) // I understand that, compiler doesn't bother about the // array index and converts them to int *a, int *b { a = b ; // At this point, how ever assignment operation is valid. } int main() { int a[] = { 1,2 }; int b[] = { 3,4 }; foo( a, b ); a = b; // Why is this invalid here. return 0; } Is it because, array decays to a pointer when passed to a function foo(..), assignment operation is possible. And in main, is it because they are of type int[] which invalidates the assignment operation. Doesn't a,b in both the cases mean the same ? Thanks. Edit 1: When I do it in a function foo, it's assigning the b's starting element location to a. So, thinking in terms of it, what made the language developers not do the same in main(). Want to know the reason.

  Read the article

• Custom class deallocated as soon as the app starts.

  - by Tangrs

  Heya, I've added a class object to the nib file. All connections are made. But for some reason, the object is deallocated as soon as it's created. Here's the code: control.h: #import <Foundation/Foundation.h> @interface control : NSObject { IBOutlet UILabel *PlayerScore; } -(IBAction) addPoint: sender; -(void) dealloc; @end control.m: #import "control.h" @implementation control -(IBAction)addPoint: sender { NSLog(@"Ohhai. Didn't crash."); //Doesn't even make it to this stage. int i = [PlayerScore.text intValue]; PlayerScore.text=[NSString stringWithFormat: @"%d",++i]; } -(void) dealloc { NSLog(@"ZOMGWTF?"); [super dealloc]; } @end Here is the console log: [Session started at 2010-06-09 19:47:57 +1000.] 2010-06-09 19:47:58.771 App[91100:207] ZOMGWTF? And after I click the button which messages addPoint, of course, it crashes. 2010-06-09 19:47:59.703 App[91100:207] * -[control] performSelector:withObject:withObject:]: message sent to deallocated instance 0x3843d80 Does anyone have any ideas?

  Read the article

• Would there be a market for this idea (cross platform VM for iPhone OS)

  - by Tzury Bar Yochay

  For a long time I wondered if the following idea worth a nickel or just a waste of time and energy. I am willing to start a project which will provide a kind of a VM for all iPxxx apps - so developed once for iPxxx can run on a Macbook, iMac, Linux, Android and windows (desktop and mobile). You get the idea, right? I want to do to the current iPhone SDK, the same as what Mono did to Microsoft .Net and perhaps a more complete set of implementation. I tend to believe that if overnight all apps on appstore become available on the android market as well that would be a mini revolution. Think about running iPad apps on every tablet that will come out to the market in the future. Wouldn't it be fantastic to all the developers, which from now on, can write once and sell everywhere? The main questions which I ask myself repeatedly is: "Is This Legal?" - I mean, say I have done this, would apple's lawyers will start sending me all kinds of nasty emails? I am willing to hear your opinion about this idea as well as if some of you willing and able to join forces and start this open source project.

  Read the article

• redirecting _top page from asp:login control in iframe onloggedin

  - by jumpdart

  So yeah, Im building a little authenticated content(.NET app) to a large html site managed by another group. They are only comfortable with managing html so all my app content will be contained in iframes. Everything is working fine as far as navigation and calling services and whatnot but i cant bust out of the frame with my asp:login control. Im trying to register some JS on logged in but with no success. Thanks protected void login_LoggedIn(object sender, EventArgs e) { StringBuilder strScript = new StringBuilder(); strScript.Append("<script language='javascript'>"); string sHome = ConfigurationManager.AppSettings["AppHomePageURL"].ToString(); //strScript.AppendFormat("window.navigate('{0}');", sHome); //strScript.AppendFormat("parent.location.href='{0}';", sHome); //strScript.AppendFormat("window.open('{0}', '_top', '', false);", sHome); strScript.AppendFormat("top.location.href='{0}';", sHome); strScript.Append("WTF_let_me_outa_here();"); strScript.Append("</script>"); ClientScript.RegisterClientScriptBlock(typeof(Page), "LoginGO", strScript.ToString()); }

  Read the article

• Would like some modelling tips for dependent values

  - by orjan

  I'm working on a model for a simple fishing competition and I have some issues with my design. The main class for the fishing game is Capture and it looks like this: public class Capture : Entity { public virtual int Weight { get; set; } public virtual int Length { get; set; } public virtual DateTime DateForCapture { get; set; } public virtual User CapturedBy { get; set; } public virtual Species Species { get; set; } } So far there´s no problem but I'm not really sure how to model the game. Every Species is connected to a reference weight that changes from year to year The number of point for a capture is its Weight divided by the current reference weight for the species. One way to solve the problem is to connect a capture to SpeciesReferenceWeight instead of Species public class SpeciesReferenceWeight : Entity { public virtual Species Species { get; set; } public virtual int ReferenceWeight { get; set; } public virtual int Year { get; set; } } But in that way that Capture is connected to the implementation details of the game and from my point of view a capture is still a capture even if it's not included in a game. The result I'm aiming for is like: http://hornalen.net/fishbonkern/2007/ that I wrote a couple of years ago with brute force sql and no domain model. I would be very happy for all kinds of feeback on this issue.

  Read the article

• Unable to `submit()` an html form after intercepting the submit with javascript.

  - by Ross Rogers

  I'm trying to intercept the submission of a form in order to change the value of my keywords label. I have the following code: <HTML> <FORM name="searchForm" method="get" action="tmp.html" > <input type="label" name="keywords" /> <input type="button" name="submit" value="submit" onclick="formIntercept();"/> </FORM> <SCRIPT language="JavaScript"> document.searchForm.keywords.focus(); function formIntercept( ) { var f = document.forms['searchForm']; f.keywords.value = 'boo'; f.submit(); }; </SCRIPT> </HTML> When I run this in chrome and click the submit button the keywords label changes to boo, but the javascript console says: Uncaught TypeError: Property 'submit' of object <#an HtmlFormElement> is not a function. How can I submit the form with the manipulated keywords?

  Read the article

• Filling in uninitialized array in java? (or workaround!)

  - by AlexRamallo

  Hello all, I'm currently in the process of creating an OBJ importer for an opengles android game. I'm relatively new to the language java, so I'm not exactly clear on a few things. I have an array which will hold the number of vertices in the model(along with a few other arrays as well): float vertices[]; The problem is that I don't know how many vertices there are in the model before I read the file using the inputstream given to me. Would I be able to fill it in as I need to like this?: vertices[95] = 5.004f; //vertices was defined like the example above or do I have to initialize it beforehand? if the latter is the case then what would be a good way to find out the number of vertices in the file? Once I read it using inputstreamreader.read() it goes to the next line until it reads the whole file. The only thing I can think of would be to read the whole file, count the number of vertices, then read it AGAIN the fill in the newly initialized array. Is there a way to dynamically allocate the data as is needed?

  Read the article

• Need help in javascript

  - by raja

  Hi: I am getting the error for the below code. Please help me out. <html><head> <title>(Type a title for your page here)</title> <script language=JavaScript> function check_length(my_formm,fieldName) { alert(fieldName); alert(document.my_formm.fieldName.value); } </script> </head> <body> <form name=my_form method=post> <input type="text" onKeyPress=checkCompanyName(); onChange=check_length("my_form","my_text"); name=my_text rows=4 cols=30 value=""> <br> <input size=1 value=50 name=text_num> Characters Left </form> </body> </html>

  Read the article

• HTML5 Local Storage of audio element source - is it possible?

  - by andrewdotcom

  Hi stackoverflow experts I've been experimenting with the audio and local storage features of html5 of late and have run into something that has me stumped. I'd like to be able to cache or store the source of the audio element locally to enable speedier and offline playback. The problem is I can't see how this is possible with the current implementation. I have tried the following using webkit: Creating a manifest file to set up local caching but the audio file appears not to be a cacheable item maybe due to the way it is stream or something I have also attempted to use javascript to put an audio object into local storage but the size of the mp3 makes this impossible due to memory issues (i think). I have tried to use the data uri and base64 to use the html as a audio transport that can be cached but again the filesize makes this prohibitive. Also the audio element does not seem to like this in webkit (works fine in mozilla) I have tried several methods of putting the data into the local database store. Again suffering the same issues as the other cases. I'd love to hear any other ideas anyone may have as to how I could achieve my goal of offline playback using caching/local storage in webkit.

  Read the article

• How can I integrate advanced computations into a database field?

  - by ciclistadan

  My biological research involves the measurement of a cellular structure as it changes length throughout the course of observation (capturing images every minute for several hours). As my data sets have become larger I am trying to store them in an Access database, from which I would like to perform various queries about their changes in size. I know that the SELECT statement can incorporate some mathematical permutations, but I have been unable to incorporate many of my necessary calculations (probably due to my lack of knowledge). For example, one calculation involves determining the rate of change during specifically defined periods of growth. This calculation is entirely dependent on the raw data saved in the table, therefore I didn't this it would be appropriate to just calculate it in excel prior to entry into the field. So my question is, what would be the most appropriate method of performing this calculation. Should I attempt to string together a huge SELECT calculation in my QUERY, or is there a way to use another language (I know perl?) which can be called to populate the new query field? I'm not looking for someone to write the code, just where is it appropriate to incorporate each step. Also, I am currently using Office Access but would be interested in any mySQL answers as I may be moving to this platform at a later date. Thanks all!

  Read the article

• Implementing comparision operators via 'tuple' and 'tie', a good idea?

  - by Xeo

  (Note: tuple and tie can be taken from Boost or C++11.) When writing small structs with only two elements, I sometimes tend to choose a std::pair, as all important stuff is already done for that datatype, like operator< for strict-weak-ordering. The downsides though are the pretty much useless variable names. Even if I myself created that typedef, I won't remember 2 days later what first and what second exactly was, especially if they are both of the same type. This gets even worse for more than two members, as nesting pairs pretty much sucks. The other option for that is a tuple, either from Boost or C++11, but that doesn't really look any nicer and clearer. So I go back to writing the structs myself, including any needed comparision operators. Since especially the operator< can be quite cumbersome, I thought of circumventing this whole mess by just relying on the operations defined for tuple: Example of operator<, e.g. for strict-weak-ordering: bool operator<(MyStruct const& lhs, MyStruct const& rhs){ return std::tie(lhs.one_member, lhs.another, lhs.yet_more) < std::tie(rhs.one_member, rhs.another, rhs.yet_more); } (tie makes a tuple of T& references from the passed arguments.) Edit: The suggestion from @DeadMG to privately inherit from tuple isn't a bad one, but it got quite some drawbacks: If the operators are free-standing (possibly friends), I need to inherit publicly With casting, my functions / operators (operator= specifically) can be easily bypassed With the tie solution, I can leave out certain members if they don't matter for the ordering Are there any drawbacks in this implementation that I need to consider?

  Read the article

• Server side method not getting called

  - by Rangel Fernandes

  From the below javascript code i am trying to call a serverside method, but serververside method is not getting called. I am using jquery, ajax <script type="text/javascript" src="JquryLib.js"></script> <script type="text/javascript" language="javascript"> function fnPopulateCities() { debugger; var State = $("#ddlState").val(); GetCities(State); return false; } function GetCities(StateId) { debugger; var v1 = 'StateId: ' + StateId; $.ajax( { type: "POST", url: 'DropDownList_Cascade.aspx/PopulateCities', data: '{' + v1 + '}', contentType: "application/json; charset=utf-8", dataType: "json", success: function (result) { if (result.status === "OK") { alert('Success!!'); } else { fnDisplayCities(result); } }, error: function (req, status, error) { alert("Sorry! Not able to retrieve cities"); } }); } </script> This is my serverside method which i need to call. private static ArrayList PopulateCities(int StateId) { //this code returns Cities ArrayList from database. } It is giving me the following error: 500 (Internal Server Error) I cannot figure out what is wrong. please help! Stack Trace: [ArgumentException: Unknown web method PopulateCities.Parameter name: methodName]

  Read the article

• Generic delegate instances

  - by Luc C

  I wonder if C# (or the underlying .NET framework) supports some kind of "generic delegate instances": that is a delegate instance that still has an unresolved type parameter, to be resolved at the time the delegate is invoked (not at the time the delegate is created). I suspect this isn't possible, but I'm asking it anyway... Here is an example of what I'd like to do, with some "???" inserted in places where the C# syntax seems to be unavailable for what I want. (Obviously this code doesn't compile) class Foo { public T Factory<T>(string name) { // implementation omitted } } class Test { public void TestMethod() { Foo foo = new Foo(); ??? magic = foo.Factory; // No type argument given here yet to Factory! // What would the '???' be here (other than 'var' :) )? string aString = magic<string>("name 1"); // type provided on call int anInt = magic<int>("name 2"); // another type provided on another call // Note the underlying calls work perfectly fine, these work, but i'd like to expose // the generic method as a delegate. string aString2 = foo.Factory<string>("name 1"); int anInt2 = foo.Factory<int>("name 2"); } } Is there a way to actually do something like this in C#? If not, is that a limitation in the language, or is it in the .NET framework?

  Read the article

• I can't seem to figure out type variables mixed with classes.

  - by onmach

  I pretty much understand 3/4 the rest of the language, but every time I dip my feet into using classes in a meaningful way in my code I get permantently entrenched. Why doesn't this extremely simple code work? data Room n = Room n n deriving Show class HasArea a where width :: (Num n) => a -> n instance (Num n) => HasArea (Room n) where width (Room w h) = w So, room width is denoted by ints or maybe floats, I don't want to restrict it at this point. Both the class and the instance restrict the n type to Nums, but it still doesn't like it and I get this error: Couldn't match expected type `n1' against inferred type `n' `n1' is a rigid type variable bound by the type signature for `width' at Dungeon.hs:11:16 `n' is a rigid type variable bound by the instance declaration at Dungeon.hs:13:14 In the expression: w In the definition of `width': width (Room w h) = w In the instance declaration for `HasArea (Room n)' So it tells me the types doesn't match, but it doesn't tell me what types it thinks they are, which would be really helpful. As a side note, is there any easy way to debug an error like this? The only way I know to do it is to randomly change stuff until it works.

  Read the article

• what are good ways to implement search and search results using ajax?

  - by Amr ElGarhy

  i have some text box in a page and in the same page there will be a table 'grid' like for holding the search result. When the user start editing and of the textbox above, the search must start by sending all textboxs values to the server 'ajax', and get back with the results to fill the below grid. Notes: This grid should support paging, sorting by clicking on headers and it will contains some controls beside the results such as checkboxs for boolean values and links for opening details in another page. I know many ways to do this some of them are: 1- updatepanel around all of these controls and thats it "fast dirty solution" 2- send the search criteria using ajax request using JQuery post function for example and get back the JSON result, and using a template will draw the grid "clean but will take time to finish and will be harder to edit later". 3- .... My question is: What do you think will be the best choice to implement this scenario? because i face this scenario too much, and want to know which implementation will be better regarding performance, optimization, and time to finish. I just want to know your thoughts about this issue.

  Read the article

• Slowing process creation under Java?

  - by oconnor0

  I have a single, large heap (up to 240GB, though in the 20-40GB range for most of this phase of execution) JVM [1] running under Linux [2] on a server with 24 cores. We have tens of thousands of objects that have to be processed by an external executable & then load the data created by those executables back into the JVM. Each executable produces about half a megabyte of data (on disk) that when read right in, after the process finishes, is, of course, larger. Our first implementation was to have each executable handle only a single object. This involved the spawning of twice as many executables as we had objects (since we called a shell script that called the executable). Our CPU utilization would start off high, but not necessarily 100%, and slowly worsen. As we began measuring to see what was happening we noticed that the process creation time [3] continually slows. While starting at sub-second times it would eventually grow to take a minute or more. The actual processing done by the executable usually takes less than 10 seconds. Next we changed the executable to take a list of objects to process in an attempt to reduce the number of processes created. With batch sizes of a few hundred (~1% of our current sample size), the process creation times start out around 2 seconds & grow to around 5-6 seconds. Basically, why is it taking so long to create these processes as execution continues? [1] Oracle JDK 1.6.0_22 [2] Red Hat Enterprise Linux Advanced Platform 5.3, Linux kernel 2.6.18-194.26.1.el5 #1 SMP [3] Creation of the ProcessBuilder object, redirecting the error stream, and starting it.

  Read the article

< Previous Page | 701 702 703 704 705 706 707 708 709 710 711 712  | Next Page >