synchronization

Class for mantain a thread safe cache

Hi, I'm developing a thread safe class that I'll use as cache, it should work in .NET and Mono. The items have a time to live, and every time that a object is retrieved, its time to live is refreshed. Each time that I add a item, the timestamp is added to another collection that holds the same keys. A timer raises the method that look...

How to use TestAndSet() for solving the critical section problem?

I'm studying for an exam and I'm having difficulty with a concept. This is the pseudo code I am given: int mutex = 0; do { while (TestAndSet(&mutex)); // critical section mutiex = 0; // remainder section } while (TRUE); My instructor says that only two of the three necessary conditions (mutual exclusion, progress, and bounded ...

Creating a Cross-Process EventWaitHandle

I have two windows application, one is a windows service which create EventWaitHandle and wait for it. Second application is a windows gui which open it by calling EventWaitHandle.OpenExisting() and try to Set the event. But I am getting an exception in OpenExisting. The Exception is "Access to the path is denied". windows Service code ...

Suitable method for Synchronizing Data between Offline and online application

Hi, I am here to ask about a way to handle data between two databse servers. I have my one application running in my city office and another in country office. My City office has got regular[ un-interrupted ] internet connection but my country office do not have. It gets connected to internet in evening time once a day only. I have ...

linux thread synchronization

I am new to linux and linux threads. I have spent some time googling to try to understand the differences between all the functions available for thread synchronization. I still have some questions. I have found all of these different types of synchronizations, each with a number of functions for locking, unlocking, testing the lock, ...

Eclipse / Aptana File Sync Solutions

Our development team uses Eclipse + Aptana to do their web development work. Currently, most of them are mapping their Eclipse projects directly to the web server. I'd rather them create a local project and use that to sync to the web server project directory they are working on. The issue is that there aren't any good solutions whi...

Is this a correct Interlocked synchronization design?

I have a system that takes Samples. I have multiple client threads in the application that are interested in these Samples, but the actual process of taking a Sample can only occur in one context. It's fast enough that it's okay for it to block the calling process until Sampling is done, but slow enough that I don't want multiple threa...

How to Lock a file and avoid readings while it's writing

My web application returns a file from the filesystem. These files are dynamic, so I have no way to know the names o how many of them will there be. When this file doesn't exist, the application creates it from the database. I want to avoid that two different threads recreate the same file at the same time, or that a thread try to return...

Efficient reliable incremental HTTP multi-file (or whole directory) upload software

Imagine you have a web site that you want to send a lot of data. Say 40 files totaling the equivalence of 2 hours of upload bandwidth. You expect to have 3 connection losses along the way (think: mobile data connection, WLAN vs. microwave). You can't be bothered to retry again and again. This should be automated. Interruptions should not...

Sync Framework Peer Data Sharing Unable to Catch Conflicts, Source Provider Alwasy wins!

Hi, I am using SQL Server 2008 and the WebSharingAppDemo-SqlProviderEndToEnd sample and this is almost perfect for my needs however I am unable to detect conflicts. By default ConflictResolutionPolicy is set to ApplicationDefined. I have tried setting the ResolutionPolicy to SourceWins, DestinationWins or ApplicationDefined and I alwa...

Is there a way to sync (two way) tables betwen a mysql server and a local MS Access?

Help me figure out a solution to a (not so unique) problem. My research group has gps devices attached to migratory animals. Every once in a while, a research tech will be within range of an animal and will get the chance to download all the logged points. Each individual spits out a single dbf and new locations are just appended to the...

Java RMI method synchronization

Hello, I have a class that is stored on the 'server' and multiple clients can call this method. This method returns a class. Now when clients call accessor methods within this class for example a set accessor method. I want the object on the server to be updated and synchronized across all the other clients. How do I use: public synch...

Synchronized IEnumerator<T>

I'm putting together a custom SynchronizedCollection<T> class so that I can have a synchronized Observable collection for my WPF application. The synchronization is provided via a ReaderWriterLockSlim, which, for the most part, has been easy to apply. The case I'm having trouble with is how to provide thread-safe enumeration of the col...

WCF security when it is used with sync services

I am using following architecture for sync process. http://www.codeproject.com/KB/smart/sync_services.aspx And for server i use WCF service, can anybody guide me how can i secure my wcf service without using certificate that is hosted on IIS. Can i get a way to pass credential or some token to authenticate? I need to authenticate and...

Logging strategy vs. performance

Hi, I'm developing a web application that has to support lots of simultaneous requests, and I'd like to keep it fast enough. I have now to implement a logging strategy, I'm gonna use log4net, but ... what and how should I log? I mean: How logging impacts in performance? is it possible/recomendable logging using async calls? Is better ...

How to sync with eclipse target management?

I've been using the Jcraft SFTP plugin for Team Synchronisation up till now but I ran across a rumour it's being deprecated by "Target Management". Still, despite my best efforts I haven't found any information on HOW you are supposed to setup a sync with RSE/Target Management. Can anybody provide a step-by-step guide or at least clarifi...

SQL Server and distributed databases. How synchronize?

Hello everyone, I'm planning a project for managing multiple distributed databases and I am raising the question of how to efficiently synchronize the data. The project will be developed with technology. NET and SQL Server. There will be a local database in which the company will load data, some of these data (not all) should be synchr...

what libraries or platforms should I use to build web apps that provide real-time, asynchronous data synchronization between clients?

This is a less a question with a simple, practical answer and more a question to foster discussion on the real-time data exchange topic. I'll begin with an example: Google Wave is, at its core, a real-time asynchronous data synchronization engine. Wave supports (or plans to support) concurrent (real-time) document collaboration, discon...

Read a value being manipulated in different thread

Hi... I'm trying to read a static property from a static class, which is being modified from a different thread. Basically I have this static class: public static class Progress{ public static int currentProgress{get; set;} } and this thread manipulating the currentProgress: private void Job(){ for(int i = 0; i<100; i++){ ...

GWT synchronization

i'm doing a function in gwt it sends an IQ stanza into a server and has to wait for the server answer in the function i make the handler that waits for the answer from the server to that IQ stanza so what i need is for the function to wait until i get the response from the server and after that do other stuff i'm a beginner in gwt so ...