How to write a memory manager that displays 4 GB for Delphi

Question

I have an object that uses more than 2 gigabytes of virtual memory. But Delphi is only 2 GB managers. I consider the ether, making a number of objects and grouping them, and using the wow64 Windows method, how and how to use 64-bit windows. Or just upgrade your memory manager to 4 GB and create it around Int64. effectively I need a TStream as a base object using Int64 instead of integers.

Answer 1

Lexdean, you say:

I need a TStream as a base object using Int64 instead of integers

Well, then you were lucky (twice) because:

• Delphi TStream uses Int64 for position, it can access files much more than 4Gb.
• If the TStream interface is enough, you can write your own TStream to do whatever you want, you do not need to wait for your own 64-bit Delphi compiler.

But if I have to answer the question in the title:

How to write a memory manager that displays 4 gigabytes for Delphi

There is no way to do this with a 32-bit compiler. Join the crowd of people asking for a 64-bit Delphi compiler!

Answer 2

Having one 2 gigabyte object is not a good idea. If the memory is fragmented, you cannot allocate it, even if there is enough free memory. I would suggest that you are trying to use a list of smaller objects.

(I remember how in Turbo Pascal (Delphi's predecessor) a variable could not be more than 64 kilobytes ... Oh, times ...;)

Answer 3

Unfortunately, the Delphi compiler does not yet compile 64-bit code. However, you can get more out of your 32-bit address space if you put {$SetPeFlags IMAGE_FILE_LARGE_ADDRESS_AWARE} in DPR. It sets a flag in the PE header, which lets Windows know that it can allocate more than 2 GB of virtual memory for it.

Guffa is right. If your object is trying to capture 2GB + of continuous memory, you are probably doing something wrong. What are you trying to do? Maybe there is an easier way ...

Answer 4

You can use the AWE API to access more memory in win32 applications. But you should think that your code is around AWE instead of adapting AWE to your code. I mean, you can write TAWEMemoryStream ... but this is not a good idea.