windows 7 3gb switch

[mkz]

I have windows 7 ultimate 64 bit with 8GB of ram. I have a 32 bit application that needs between 2 and 3gb of ram, but the user space seems to be limited to 2gb. Is there a way to give 32 bit applications for than 2gb of virtual address space? I assume kernel space is not an issue since the OS is actually 64 bit.

BCDEdit didnt seem to work.

 

[logicearth]

The application must be Large Address Aware. If not...64bit versions of Windows implicitly set the "3GB Switch" so that does not need to be done.

 

[cluberti]

+1 - a 32bit app running inside the WOW64 subsystem actually can have access to 4GB of VA if it was compiled with the /LARGEADDRESSAWARE linker property when built. If not, it will only have access to 2GB of VA, just as that app would on a 32bit system - there is no difference here. /3GB inside WOW64 is implicit, because there's no kernel VA that needs to be shared (hence a 32bit LAA app can access all 4GB of the 32bit VA space inside the WOW64 container).

You *can* edit an application with editbin.exe from Visual Studio to add /LARGEADDRESSAWARE to the image properties, but there are caveats - the app could become unstable afterwards, and any application compiled with the /GL linker option cannot be edited by editbin at all. Also, you need Visual Studio installed to get access to the editbin and dumpbin tools (dumpbin can dump out an image's headers, showing you whether or not an application was indeed compiled LAA or not).

 

[gendoikari1]

I remember there was a fix for Supreme Commander/S.T.A.L.K.E.R/Oblivion that gave the .exe /LARGEADDRESSAWARE, in order to use it all that needs to be done is to edit the Startme.bat in here: