KB0005: Very large IDB files and how to deal with them on Windows

Usually IDA Pro has a 2GB memory limit, this makes importing/diffing large IDBs larger then ~100.000 functions impossible. To be able to import/diff IDBs which are larger you have the option to change IDAs memory limites on systems with more then 2GB of main memory installed. For this precedure you need EDITBIN.exe from the visual studio C/C++ Build Tools. The following command line statement will change the default memory behavior of the idaq.exe file:

editbin.exe /LARGEADDRESSAWARE C:\where_ever_you_installed_ida\idaq.exe

This should enable you to export/diff very large IDBs with a function count around 200.000 function. Note that, the function count is only a very rough measurement.