Large File Copy Operation Causes Available Bytes to Drop Significantly

SYMPTOMS

A large file copy operation causes available bytes to drop significantly. This happens when a Windows client copies a large file from or to a Windows NT computer.

In this case, you will notice a user interface performance degradation. The files need to be about the size of the physical memory of the computer or greater.

If you look at performance counters while this happens, you find that the counter for the file cache (Memory: Cache Bytes) goes up while the process working sets (Process: Working Set, instance _Total) decline. Available bytes (Memory: Available Bytes) declines in the inverse proportion of the cache bytes.