Allocating more than 1,000 MB of memory in 32-bit .NET process

Question

I am wondering why I\'m not able to allocate more that 1,000 MB of memory in my 32-bit .NET process. The following mini application throws an OutOfMemoryException after havi

Answer 1

The virtual address space limit of a Win32 process is 1.5GB (not entirely true). Additionally in the .NET frameworks there is a limiter to the % of memory a .NET process can consume. The machine.config has a processModel element with an attribute memoryLimit which is the % of available memory a process can consume. The default value is 60%.

If the machine you're running on has 2GB of memory or you haven't enabled the /3GB switch in your BOOT.INI then you're going to get ~1.3GB of memory per process.

I can't find the KB article but if I remember correctly .NET 1.x cannot address beyond the 1.5GB (1.8GB?) limit regardless of your settings.

http://blogs.msdn.com/tmarq/archive/2007/06/25/some-history-on-the-asp-net-cache-memory-limits.aspx http://social.msdn.microsoft.com/Forums/en-US/clr/thread/c50ea343-b41b-467d-a457-c5a735e4dfff http://www.guidanceshare.com/wiki/ASP.NET_1.1_Performance_Guidelines_-_Caching#Configure_the_Memory_Limit