Gb Feature Considerations; Enabling The 3 Gb Feature On 32-Bit Machines - Autodesk 24000-000000-9860 - Revit Architecture - PC User Manual

If you receive a message that the current session's memory usage is approaching the operating system
limit, save your work as soon as possible and restart Revit Architecture. If you are using a workshared
environment, save your local file, restart Revit Architecture, and then save to central.
Enable the 3 GB feature on your Windows
See

Enabling the 3 GB Feature on 32-Bit Machines

Run Revit Architecture on a Windows 64-bit operating system.
Reduce the number of loaded DWG and RVT links. See
Reduce the number of loaded RVT and RFA files. See
Limit the number of views open. If you have multiple views open, you can quickly close all hidden views
by clicking Window menu

3 GB Feature Considerations

Before deciding to use the 3 GB feature, review the following considerations:
This feature is supported only on Windows XP SP2 and Windows Vista running on 32-bit machines.
When the 3 GB feature is enabled, your operating system has less memory space. It is not completely
clear what implications this may have on Windows, so be cautious with regard to the total application
load placed on Windows while running in this mode. If you do not require the larger address space, it
is recommended that you do not enable this option.
At least one graphics card driver version is known not to work with 3 GB. This is ATI Fire GL 8800, driver
version 6.12.10.3035. If you experience a crash, restart your computer without the /3GB option and
check whether upgrading to the latest graphics card driver resolves the issue.
Enabling the 3 GB Feature on 32-Bit Machines
Revit Architecture is a 32-bit application, which is limited to 4 GB of virtual address space. Typically, on a
32-bit machine, Microsoft
operating system and leaves the remaining 2 GB for the application process (including the space for the
code pages, the stack, and all dynamically allocated memory). The 3 GB feature divides the virtual address
space differently on 32-bit machines, providing 3 GB for the application and 1 GB for the operating system.
On 64-bit machines, the 3 GB switch does not apply because Windows does not reserve virtual address space
for the operating system, allowing Revit Architecture to use up to the available 4 GB.
Before enabling the 3 GB feature, see
To enable the 3 GB feature on Windows XP
1 Open the boot.ini file.
2 In the "operating systems" section, copy the original line containing the boot path, then modify
16 | Chapter 1 Welcome to Revit Architecture 2009
Close Hidden Windows.
®
Windows
This file is typically located in C:\boot.ini.
the copied line to add the option (/3GB) and the display string that identifies the boot option.
An example of the line to copy and the modified version of the line are shown below. The
modified portions of the copied line are in bold.
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional"
/fastdetect
®
operating system to improve performance on 32-bit machines.
on page 16.
Managing Links
Purging Unused Families
®
reserves 2 GB of the 4 GB virtual address space of any process for the
3 GB Feature Considerations
on page 1222.
on page 436.
on page 16.