Consider this JDK standard interface: public interface ReadWriteLock{ public Lock readLock(); public Lock writeLock(); } B. Goetz in Java Concurrency in practice mentioned upgrading from readL...

I read that a write lock is exclusive and a read lock is shared , so a piece of code which in readlock anyway can be accessed by multiple threads . What if no read lock is acquired by the threads i...

I have a set of data structures I need to protect with a readers/writer lock. I am aware of boost::shared_lock, but I would like to have a custom implementation using std::mutex, std::condition_var...

When I read the documentations of Mutex and RwLock, the difference I see is the following: Mutex can have only one reader or writer at a time, RwLock can have one writer or multiple readers at a t...

I have a hash table data structure that I wish to make thread safe by use of a reader/writer lock (my read:write ratio is likely somewhere in the region of 100:1). I have been looking around for h...

From ReentrantLock javadoc: Fair mode When constructed as fair, threads contend for entry using an approximately arrival-order policy. When the currently held lock is released either the lon...

When synchronizing access to a shared resource, is there ever a reason not to use a read/write lock instead of a vanilla mutex (which is basically just a write lock), besides the philosophical reas...

I have some data structure, in which I want to exclusively lock the access for writing, but to enable parallel access for reading. I made some searches and found out the classes ReadWriteLock and ...

I try to prove that synchronized is slower when there are many readers and only some writers. Somehow I proved the opposite. The RW example, time of execution is 313 ms: package zad3readWriteLock...

We have found that we have several spots in our code where concurrent reads of data protected by a mutex are rather common, while writes are rare. Our measurements seem to say that using a simple m...

I think I'm misunderstanding how the FileChannel's locking features work. I want to have an exclusive write lock on a file, but allow reads from any process. On a Windows 7 machine running Java 7, ...

I'm using QReadWriteLock in recursive mode. This code doesn't by itself make sense, but the issues I have arise from here: lock->lockForWrite(); lock->lockForRead(); lockForRead is blocke...

The following is the typical reader and writer pattern (a lot of reads and few writes) private ReadWriteLock lock = new ReentrantReadWriteLock(); private int value; public void writeValue(int ...

Consider a primitive type variable with lots of threads reading and a few threads writing, will the following code work correctly? If it will, does it provide better performance than 1). declaring...

I am working on Workflow like system. I have one task table and status field. Value for status can be one of New,ready,processing,error,abort,done. I have about 7 processes which will be triggered...

I'm looking for en efficient system to have a series of read/write locks organized hierarchically to manage access to hierarchically organized resources. If a subtree is locked for write, then no o...