The IIS Object cache is used to store hard to retrieve items such as file handles, Directory listings, and parsed Internet Database Connector queries and their results.

By default, the size of the cache is set at 10% of physical memory.

You can configure the cache size by editing:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\InetInfo\Parameters

and edit or Add Value of MemoryCacheSize which is a type REG_DWORD. A value of 0 disables the cache (bad idea) while any other value in bytes is valid.

Stop and start the IIS service or reboot.