synchronization

I was wondering about the best practices in synchronizing multiple azure instances that run the same role. More precisely, I want to prevent several worker roles to work on the same work-unit. Azure queues do not seem to help on this matter. One option is to use an sql table with locks and stored procedures; but using sql synchronization in Azure seems a bit awkward. Any ideas? Edit, my detailed(but simplified problem) is as follows: There are n targets. A unit of work must be done on each target at a specified interval (say 30 seconds - but it is different for each target). I have m workers

We have a dev server which contains a collection of Objects. The actual accumulation of these objects is an ongoing process, which runs a whole process of labelling, verification, etc. on this local dev server. Once these objects are production ready, they are added to the Production DB, which will from that moment, use them in its calculations. I'm looking for a way to simply add the delta (new objects) into the production DB, while retaining all the other collections, and older objects in the same collection as is. Until now, we've used MySql, so this process simply involved running DB

lets say Thread-1 synchronizes on object synchronize(object){ //statement1 //statement2 //statement3 } what happens to the lock on object if Thread-1 crashes on statement2, will JVM release the lock on Thread-1 automatically when this happens ? because otherwise if Thread-2 is wating for the lock on object to be released and Thread-1 crashes, the Thread-2 will wait forever. It is defined in the JLS #14.19 : synchronized ( Expression ) Block If execution of the Block completes abruptly for any reason, then the monitor is unlocked and the synchronized statement completes abruptly for the same

We are using git for a multi site project and both the repo and the team have grown substantially. Therefore remote sites are suffering. I would like to add new git servers to the remote sites to decrease the load on our git server and to make the downloads faster. However I am not sure how to keep these synchronized. Is there any way to replicate git servers atomically? And if not any other suggestions? You could have a main "write" repo, and multiple remote, read only , repos pull from that. In turn, remote users would pull from those. That would give you increased download speeds from

I'm mostly familiar with Java, C and C++ in which there are ways to control that only one thread is accessing a resource at any given time. Now I'm in search for something similar but in PHP 5.x. To formulate my problem with one example: I have an ASCII-file which only stores a number, the value of a page load counter. At application deployment the file will simply hold a 0. For each access the value will be incremented by one. The goal is to keep track of page loads. The problem comes when many users are concurrently accessing the page containing the counter. When thread A has read the

Do methods that only use local variables inside suffer any threading issues ?. Somewhere it was mentioned that the method with local variables are copied to each thread stack frame to work with and do not need to synchronized for multithreaded implementation unless it uses class level or static references/variables ? JUST MY correct OPINION If your method only operates on parameters and locally-defined (as opposed to class member) variables then there are zero synchronization problems to worry about. But... This means any mutable reference types you use must live and die only within the scope

Does anyone know of any books or online resources (except the dev docs) that cover the Sync Adapter and its usage? Struggling to find any good material myself. Or.. does anyone know of any alternative libraries for conducting remote sync services? Thanks There really isn't any good resources at this point. If I had to guess at why, it is because the actual implementation of a sync is going to be very specific to each app. I am writing one right now, and it is very trial and error. We could definitely benefit from a good tutorial on some of the more well known api's out there (an implementation

I have a C# application wherein there are two multiline textboxes side-by-side, each in one side of a split-container. I would like to synchronize their vertical scroll, so that when the user scrolls up or down one of the textboxes, the other textbox scrolls respectively in the same direction. Is there a way to do this? Thanks. ADDITIONAL INFORMATION - 7/26/10 I found some interesting APIs on the MSDN website: TextBox.GetFirstVisibleLineIndex Method TextBox.GetLastVisibleLineIndex Method TextBox.ScrollToLine Method The documentation there looks promising, but my compiler (Microsoft Visual C#