The Microsoft .NET Framework and Common Language Runtime (CLR) mark a significant change in how developers build applications targeting the Windows platform. In years past, developers directly manipulated system memory, allocating, initializing, moving data around and freeing blocks of memory by address pointers. This practice tended to result in fast programs, but unfortunately introduced a wide range of highly detailed and difficult-to-debug errors.
Developers can free themselves from the error-prone tedium of managing an application’s memory by using the features of the .NET Framework to do it automatically. The .NET Framework allocates memory on demand, and reclaims memory once the application is done with it. Developers can focus on solving business problems and leave memory management details to the .NET Framework.
But nothing comes for free in writing applications. It’s time-consuming to identify memory that is no longer needed, collect that memory and return it to the free memory heap. Applications that use memory poorly add to the problem, forcing the system to work harder and more often to reclaim memory. Over time, poor application memory management can also result in subtle, difficult to find errors that slow application performance while reducing scalability and reliability.
These types of memory problems are new and unfamiliar to most developers. In many cases, developers simply lack the experience and understanding to know when an application has a memory problem, and what if anything they can do about it. They assume that they have no control over how memory is used, allocated and deallocated, and pay no attention to how design and implementation decisions impact memory usage.
But there are solutions, and it’s simply a matter of learning where the problems can manifest themselves and why they occur. Even in a managed world, developers can help avoid pitfalls and improve the performance of their applications, by understanding how .NET memory management works and how their applications use memory. Developer tools that assist in this understanding, and enable developers to make informed decisions on architecting and building their applications, are an essential part of creating fast and reliable .NET applications.
