C++ High Performance

Shared memory

Threads created in the same process share the same virtual memory. This means that a thread can access any data that is addressable within the process. The operating system, which protects memory between processes using virtual memory, does nothing to protect us from accidentally accessing memory inside a process that was not intended to be shared among different threads. Virtual memory only protects us from accessing memory allocated in other processes than our own.

Sharing memory between multiple threads can be a very efficient way to handle communication between threads. However, sharing memory in a safe way between threads is one of the major challenges when writing concurrent programs in C++. You should always strive to ...