Search Results

Search found 8495 results on 340 pages for 'high availability'.

Page 227/340 | < Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >

  • How to resolve this very heavy query that slows down the application?

    - by Juan Paredes
    Hi, We have a web application running in a production enviroment and at some point the client complained about how slow the application got. When we checked what was going on with the application and the database we discover this "precious" query that was being executed by several users at the same time (thus inflicting a extremely high load on the database server): SELECT NULL AS table_cat, o.owner AS table_schem, o.object_name AS table_name, o.object_type AS table_type, NULL AS remarks FROM all_objects o WHERE o.owner LIKE :1 ESCAPE :"SYS_B_0" AND o.object_name LIKE :2 ESCAPE :"SYS_B_1" AND o.object_type IN(:"SYS_B_2", :"SYS_B_3") ORDER BY table_type, table_schem, table_name Our application does not execute this query, I believe it is an Hibernate internal query. I've found little information on why Hibernate does this extremely heavy query, so any help is very much appreciated! The production enviroment information: Red Hat Enterprise Linux 5.3 (Tikanga), JDK 1.5, web container OC4J (whitin Oracle Application Server), Oracle Database 10g Release 10.0.0.1, JDBC Driver for JDK 1.2 and 1.3, Hibernate version 3.2.6.ga. Thank you.

    Read the article

  • Suggest Cassandra data model for an existing schema

    - by Andriy Bohdan
    Hello guys! I hope there's someone who can help me suggest a suitable data model to be implemented using nosql database Apache Cassandra. More of than I need it to work under high loads and large amounts of data. Simplified I have 3 types of objects: Product Tag ProductTag Product: key - string key name - string .... - some other fields Tag: key - string key name - unique tag words ProductTag: product_key - foreign key referring to product tag_key - foreign key referring to tag rating - this is rating of tag for this product Each product may have 0 or many tags. Tag may be assigned to 1 or many products. Means relation between products and tags is many-to-many in terms of relational databases. Value of "rating" is updated "very" often. I need to be run the following queries Select objects by keys Select tags for product ordered by rating Select products by tag order by rating Update rating by product_key and tag_key The most important is to make these queries really fast on large amounts of data, considering that rating is constantly updated.

    Read the article

  • Only show activities from a specific gadget in OpenSocial

    - by corné
    I created a gadget which is able to post activities: function postActivity(text) { var params = {}; params[opensocial.Activity.Field.TITLE] = text; var activity = opensocial.newActivity(params); opensocial.requestCreateActivity(activity, opensocial.CreateActivityPriority.HIGH); }; And I request activities by doing: req.add(req.newFetchActivitiesRequest( new opensocial.IdSpec({'userId' : 'VIEWER', 'groupId' : 'FRIENDS'})), 'friends_activities'); My question is: How can I filter activities to only show activities posted by a specific gadget? I reckon the field "appId" is meant for this, but this field is empty in the response.

    Read the article

  • Quickest and easiest way to implement speech to text conversion for a small speech subset.

    - by sgtpeppers
    Hi, I want to implement a system that receives speech through a microphone on my Mac OS x. I know arbitrary speech recognition is close to impossible without training the system so I'm willing to restrict it to 10 simple sentences. It must recognize with a high degree of accuracy which of these 10 sentences are being spoken, generate the text and add an entry to a remote MySQL database. With these being the architecture of the system I want to implement, could anyone give me an overview of what would be the best way to go about implementing this system? I'm looking for ideas like open source libraries to minimize the coding as this is just a prototype application for a demonstration. Basically I'm looking for a quick and easy solution. Thanks!

    Read the article

  • Strategies to use Database Sequences?

    - by Bruno Brant
    Hello all, I have a high-end architecture which receives many requests every second (in fact, it can receive many requests every millisecond). The architecture is designed so that some controls rely on a certain unique id assigned to each request. To create such UID we use a DB2 Sequence. Right now I already understand that this approach is flawed, since using the database is costly, but it makes sense to do so because this value will also be used to log information on the database. My team has just found out an increase of almost 1000% in elapsed time for each transaction, which we are assuming happened because of the sequence. Now I wonder, using sequences will serialize access to my application? Since they have to guarantee that increments works the way they should, they have to, right? So, are there better strategies when using sequences? Please assume that I have no other way of obtaining a unique id other than relying on the database.

    Read the article

  • w3wp.exe in ASP.NET production app is using 100% CPU. How to find the problem ?

    - by Tucker
    Hi, we have an asp.net app in production where w3wp.exe is taking 100% CPU ( 4 cores - 4 threads at 25% ) and cpu load never goes down until we recycle the application pool ( the app is alone in the application pool ). Our error log has nothing, there is no exceptions being emitted ( or at least we don't catch them ) so we suspect it's code problem ( infinite loop / deadlock ). The problem only arises after some hours running with high load ( several thousand users ). There is any way to profile one of the EXISTING threads that is causing cpu load ? After taking a look to JetBrains's DotTrace Profiler seems like it's not possible for limitations of Profiling API and man, we haven't get to reproduce the problem in our testing environment. The app uses SQL Server 2005, LINQ2SQL and System.Transactions API. Any suggestion to find the problem ?

    Read the article

  • Why darcs instead of git?

    - by Ctrl Alt D-1337
    Using pure functional languages can have a lot of benefits over using impure imperatives but low level systems languages will generally allow you to achieve much greater performance especially when they are imperative because it allows you to specify the exact steps in how the cpu should compute the result. If there is ever list of tools where high performance is an absolute must then I would put source version controls systems right at the top of that list and git achieves this very well but performance is not it's only advantage over many other other types of version control systems anyway. The git team are handling the unsafe c code very well and I never worry about my type system or any other features of the language it is written in so why is it that there is a lot of haskell developers that must use darcs when they will only be using the finished product?

    Read the article

  • Subclassing UIScrollView for drawing w/o views

    - by David Dunham
    I'm contemplating subclassing UIScrollView (the way UITextView does) to draw a fairly large amount of text (formatted in ways that NSTextView can't). So far the view won't actually scroll. I'm setting contentSize, and when I drag, I see the scroll indicator. But nothing changes (and I don't get a drawRect: message). An alternate approach is to use a child view, and I've done this. The view can be over 5000 pixels high, however, and I'm a bit concerned about performance on an actual device. (The other approach, be like UITableView, would be a huge pain -- I'm "porting" Mac Cocoa code, and a collection of views would be a huge architecture change.) I've done some searching, but haven't found anyone who is using UIScrollView to do the drawing. Has anyone done this and know of any pitfalls?

    Read the article

  • JD Edwards... call C#?

    - by rbobby
    Hey all, I know very little about JD Edwards. I have a client asking how to call an API we supply (as COM, C#, REST) from JD Edwards. I'm not getting much in terms of high quality answers from their tech guy... so I thought I'd ask here. Can JD Edwards call C#? Can JD Edwards call Java? Can JD Edwards call a Unix scipt? Can anyone point me towards anything useful in terms of developer/customization documentation? Thanks!

    Read the article

  • typesafe NotifyPropertyChanged using linq expressions

    - by bitbonk
    Form Build your own MVVM I have the following code that lets us have typesafe NotifyOfPropertyChange calls: public void NotifyOfPropertyChange<TProperty>(Expression<Func<TProperty>> property) { var lambda = (LambdaExpression)property; MemberExpression memberExpression; if (lambda.Body is UnaryExpression) { var unaryExpression = (UnaryExpression)lambda.Body; memberExpression = (MemberExpression)unaryExpression.Operand; } else memberExpression = (MemberExpression)lambda.Body; NotifyOfPropertyChange(memberExpression.Member.Name); } How does this approach compare to standard simple strings approach performancewise? Sometimes I have properties that change at a very high frequency. Am I safe to use this typesafe aproach? After some first tests it does seem to make a small difference. How much CPU an memory load does this approach potentially induce?

    Read the article

  • Developing Mobile App (Iphone,Blackberry,Android) for an existing website

    - by soodos
    Hey Guys I have a website and am planning to develop a mobile version of it for the iphone, blackberry and android. My website is a social network built on PHP Zend framework. Now all these mobile apps are going to be having the same functionality like the website. I am little ignorant about this - but from a high level I understand that all these mobile apps should not have to write any backend logic. For every functionality - they will simply make a web service API call to interact with the backend. So does that mean, for every functionality I need to create a web service method. Can the existing code be re used - I'm a little lost - Can someone shed some light on this matter or point me in the right direction (like some articles) Thanks

    Read the article

  • Minimum Acceptable Code Coverage Numbers in the real world.

    - by Pita.O
    Hi, I am in the middle of putting together some guidelines around code coverage and I want to specify a number that really makes sense. It's easy to repeat the 100% mantra that I see all over the internet without considering the cost benefit analysis and when diminishing returns actually sets in. I solicit comments from persons who have actually reported code coverage on real-life, medium/large-sized projects. What percentages were you seeing? How much is too much? I really want some balance (in figures) that will help developers produce hight quality code. Is 65% coverage too low to expect? Is 80% too high?

    Read the article

  • LNK1106 with big binary resource

    - by E Dominique
    I have a rather huge .dat-file (896MB) included as a BIN resource in my project. Now I get a LNK1106 link error ("fatal error LNK1106: invalid file or disk full: cannot seek to 0x382A3920".) I use Visual Studio 2005 under Windows XP, and have tried on a 4GB RAM machine with high Virtual Memory settings and lots of disk space. I have tried a number of different optimization flags, but to no avail. Does anyone have a clue? EDIT: I have narrowed it down to a specific size of the compiled resource. If the .res file is 544078588 bytes (about 518.9MB) or larger, the error occurs. If it is smaller it works just fine. Still no solution, though...

    Read the article

  • What Simple Changes Made the Biggest Improvements to Your Delphi Programs

    - by lkessler
    I have a Delphi 2009 program that handles a lot of data and needs to be as fast as possible and not use too much memory. What small simple changes have you made to your Delphi code that had the biggest impact on the performance of you program by noticeably reducing execution time or memory use? Thanks everyone for all your answers. Many great tips. For completeness, I'll post a few important articles on Delphi optimization that I found. Before you start optimizing Delphi code at About.com Speed and Size: Top 10 Tricks also at About.com Code Optimization Fundamentals and Delphi Optimization Guidelines at High Performance Delphi, relating to Delphi 7 but still very pertinent.

    Read the article

  • PHP application variable... maybe?

    - by James
    I went to a PHP job interview, I was asked to implement a piece of code to detect visitors are bots to crawl thru the website and steal content. So I implemented a few lines of code to detect if the site is being refreshed/visited too quickly/often by using a session variable to store last visit timestamp. I got told that session varaibles can be manupilated by cookies etc, so I am wondering if there is a application variable that I can use to store the timestamp information against visitor IPs eg $_SERVER[REMOTE_ADDR]? I know that I can write the data to a file but it's not very good for a high traffic website. Regards James

    Read the article

  • OpenCL: does it play well with OpenMP, can I connect other languages to it, etc.

    - by Cem Karan
    The 1.0 spec for OpenCL just came out a few days ago (Spec is here) and I've just started to read through it. I want to know if it plays well with other high performance multiprocessing APIs like OpenMP (spec) and I want to know what I should learn. So, here are my basic questions: If I am already using OpenMP, will that break OpenCL or vice-versa? Is OpenCL more powerful than OpenMP? Or are they intended to be complementary? Is there a standard way of connecting an OpenCL program to a standard C99 program (or any other language)? What is it? Does anyone know if anyone is writing an OpenCL book? I'm reading the spec, but I've found books to be more helpful.

    Read the article

  • From admin to dev [closed]

    - by Terry
    Recently a friend of mine had gone from a high level NOC position to a developer. Before that he was just doing the help desk stuff. He has no degree, only the usual MIS/networking certifications and as far as I know only tinkers with code on the weekends. I can see where in some scenarios having a good understanding of configurations, packets, users, OU's, etc would be extremely beneficial to a developer. My question is this, how many full time developers started off this way? Even how many people dual wield the responsibility of developer/systems administrator/network administration?

    Read the article

  • Super wide, but not so tall, bitmap?

    - by Erik Karlsson
    Howdy folks. Is there any way to create a more space/resource efficient bitmap? Currently i try to render a file, approx 800 px high but around 720000px wide. It crashes my application, presumebly because of the share memory-size of the bitmap. Can i do it more efficient, like creating it as an gif directly and not later when i save it? I try to save a series of lines/rectangles from a real world reading, and i want it to be 1px per 1/100th of a second. Any input? And btw, i never manage to ogon using google open id : /

    Read the article

  • Programming tests: are they relevant?

    - by BlackVoid
    Do online programming tests have any value (except for providing an evidence to potential employers) in terms of evaluating your knowledge, or a they too broad or too narrow in general? For examples, brainbench.com and similar websites. From my experience I have never found myself scoring particularly high, although I have many years of commercial experience and is doing great at work. These tests mostly refer to things I have never worked with (WebForms or ADO .Net, who works with ADO .Net directly anyway?), yet these tests claim to be C# tests. If you were hiring a programmer, would you consider online tests as an evidence of real skill?

    Read the article

  • Code Golf: Beehive

    - by LiraNuna
    The challenge The shortest code by character count that will generate a beehive from user input. A beehive is defined a a grid of hexagons in a size inputted by the user as two positive numbers greater than zero (no need to validate input). The first number (W) represents the width of the beehive - or - how many hexagons are on each row. The second number (H) represents the height of the beehive - or - how many hexagons are on each column. A Single hexagon is made from three ASCII characters: _, / and \, and three lines: __ / \ \__/ Hexagons complete each other: the first column of the beehive will be 'low', and the second will be high - alternating and repeating in the same pattern forming W hexagons. This will be repeated H times to form a total of WxH hexagons. Test cases: Input: 1 1 Output: __ / \ \__/ Input: 4 2 Output: __ __ __/ \__/ \ / \__/ \__/ \__/ \__/ \ / \__/ \__/ \__/ \__/ Input: 2 5 Output: __ __/ \ / \__/ \__/ \ / \__/ \__/ \ / \__/ \__/ \ / \__/ \__/ \ / \__/ \__/ Input: 11 3 Output: __ __ __ __ __ __/ \__/ \__/ \__/ \__/ \__ / \__/ \__/ \__/ \__/ \__/ \ \__/ \__/ \__/ \__/ \__/ \__/ / \__/ \__/ \__/ \__/ \__/ \ \__/ \__/ \__/ \__/ \__/ \__/ / \__/ \__/ \__/ \__/ \__/ \ \__/ \__/ \__/ \__/ \__/ \__/ Code count includes input/output (i.e full program).

    Read the article

  • How to put a newline into a column header in an xtable in R

    - by PaulHurleyuk
    I have a dataframe that I am putting into a sweave document using xtable, however one of my column names is quite long, and I would like to break it over two lines to save space calqc_table<-structure(list(RUNID = c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), ANALYTEINDEX = c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), ID = structure(1:11, .Label = c("Cal A", "Cal B", "Cal C", "Cal D", "Cal E", "Cal F", "Cal G", "Cal H", "Cal High", "Cal Low", "Cal Mid"), class = "factor"), mean_conc = c(200.619459644855, 158.264703128903, 102.469121407733, 50.3551544728544, 9.88296440865076, 4.41727762501703, 2.53494715706024, 1.00602831741361, 199.065054555735, 2.48063347296935, 50.1499780776199), sd_conc = c(2.3275711264554, NA, NA, NA, NA, NA, NA, 0.101636943231162, 0, 0, 0), nrow = c(3, 1, 1, 1, 1, 1, 1, 3, 2, 2, 2)), .Names = c("Identifier of the Run within the Study", "ANALYTEINDEX", "ID", "mean_conc", "sd_conc", "nrow"), row.names = c(NA, -11L ), class = "data.frame") calqc_xtable<-xtable(calqc_table) I have tried putting a newline into the name, but this didn't seem to work names(calqc_table)[1]<-"Identifier of the \nRun within the Study" Is there a way to do this ? I have seen someone suggest using the latex function from the hmisc package to manually iterate over the table and write it out in latex manually, including the newline, but this seems like a bit of a faf !

    Read the article

  • Are "EXC_BREAKPOINT (SIGTRAP)" exceptions caused by debugging breakpoints?

    - by Dennis
    I have a multithreaded app that is very stable on all my test machines and seems to be stable for almost every one of my users (based on no complaints of crashes). The app crashes frequently for one user, though, who was kind enough to send crash reports. All the crash reports (~10 consecutive reports) look essentially identical: Date/Time: 2010-04-06 11:44:56.106 -0700 OS Version: Mac OS X 10.6.3 (10D573) Report Version: 6 Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000002, 0x0000000000000000 Crashed Thread: 0 Dispatch queue: com.apple.main-thread Thread 0 Crashed: Dispatch queue: com.apple.main-thread 0 com.apple.CoreFoundation 0x90ab98d4 __CFBasicHashRehash + 3348 1 com.apple.CoreFoundation 0x90adf610 CFBasicHashRemoveValue + 1264 2 com.apple.CoreText 0x94e0069c TCFMutableSet::Intersect(__CFSet const*) const + 126 3 com.apple.CoreText 0x94dfe465 TDescriptorSource::CopyMandatoryMatchableRequest(__CFDictionary const*, __CFSet const*) + 115 4 com.apple.CoreText 0x94dfdda6 TDescriptorSource::CopyDescriptorsForRequest(__CFDictionary const*, __CFSet const*, long (*)(void const*, void const*, void*), void*, unsigned long) const + 40 5 com.apple.CoreText 0x94e00377 TDescriptor::CreateMatchingDescriptors(__CFSet const*, unsigned long) const + 135 6 com.apple.AppKit 0x961f5952 __NSFontFactoryWithName + 904 7 com.apple.AppKit 0x961f54f0 +[NSFont fontWithName:size:] + 39 (....more text follows) First, I spent a long time investigating [NSFont fontWithName:size:]. I figured that maybe the user's fonts were screwed up somehow, so that [NSFont fontWithName:size:] was requesting something non-existent and failing for that reason. I added a bunch of code using [[NSFontManager sharedFontManager] availableFontNamesWithTraits:NSItalicFontMask] to check for font availability in advance. Sadly, these changes didn't fix the problem. I've now noticed that I forgot to remove some debugging breakpoints, including _NSLockError, [NSException raise], and objc_exception_throw. However, the app was definitely built using "Release" as the active build configuration. I assume that using the "Release" configuration prevents setting of any breakpoints--but then again I am not sure exactly how breakpoints work or whether the program needs to be run from within gdb for breakpoints to have any effect. My questions are: could my having left the breakpoints set be the cause of the crashes observed by the user? If so, why would the breakpoints cause a problem only for this one user? If not, has anybody else had similar problems with [NSFont fontWithName:size:]? I will probably just try removing the breakpoints and sending back to the user, but I'm not sure how much currency I have left with that user. And I'd like to understand more generally whether leaving the breakpoints set could possibly cause a problem (when the app is built using "Release" configuration).

    Read the article

  • What stack would you use for a new web Java project if you started today?

    - by Joelio
    If you were to start a brand new java project today with the following requirements: high scale (20k + users) you want to use something that is fairly mature (not changing dramatically) & wont be dead technology in 3 years you want something very productive (no server restarts in dev, save the code and its automatically compiled and deployed), productivity and time to market are key. some amount of ajax on front end no scripting language, jruby, groovy, php etc , has to be java has to support i8n What stack would you use & Why? (when I say stack, I mean, everything soup to nuts, so app server, mvc framework, bean framework, ORM framework, javascript framework etc...)

    Read the article

  • Mysql out of disk space

    - by Paddy
    I have just finished developing a rails app which has a mysql db as a backend. The app is meant for high traffic and will store lots of information. I am planning to set up my own web server and host the site from it. If in future my disk space runs out i would want to expand by adding more space. But say if my mysql database is housed in my /disk0s1 and by adding a new drive i have more partitions (and hence more disk space), how then would i extend my database to store information on those partitions too, and at the same time prevent any information from being written on the original partition. Should i go for multiple databases? if so how? If i went for a hosting solution i wouldn't be bothering about this as i would just have to worry about making payments for the extra space :) I always wondered how space is added on-the-go by these webhosts. Is there any specific mysql configuration that i have to make?

    Read the article

  • Difference between Apache Tapestry and Apache Wicket

    - by Stephan Schmidt
    Apache Wicket ( http://wicket.apache.org/ ) and Apache Tapestry ( http://wicket.apache.org/ ) are both component oriented web frameworks - contrary to action based frameworks like Stripes - by the Apache Foundation. Both allow you to build your application from components in Java. They both look very similar to me. What are the differences between those two frameworks? Has someone experience in both? Specifically: How is their performance, how much can state handling be customized, can they be used stateless? What is the difference in their component model? What would you choose for which applications? How do they integrate with Guice, Spring, JSR 299? Edit: I have read the documentation for both and I have used both. The questions cannot be answered sufficently from reading the documentation, but from the experience from using these for some time, e.g. how to use Wicket in a stateless mode for high performance sites. Thanks.

    Read the article

< Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >