Memory Allocation

[jeroen brouwers]

Hi,
I've seen some issues on this already, but I'm getting stuck.

What I'm trying to do is load database tables into memory for speed. I would prefer to put them all in 1 array (so 3 dimensions).
If I count the maximum values for colcount and rowcount I have to redim the global array : IDX(395,6363,165)

I believe this is still well within the maximum allowed elements for an array but of course memory is an issue here. I get an error 7. I've tried putting the first dimension on 5 which works, 10 is already a problem.
I'm having more than enough memory left (~126 MB) so that should do.

So I tried GlobalAlloc(%GMEM_FIXED, iBytes) where iBytes = 40*1024*1024 so that 40 Mb. The system monitor shows the drop but it still doesn't work.

How should I handle this?

Hope someone can help,

Jeroen Brouwers


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[Lance Edmonds]

Assuming this is just a BYTE array, it is going to take 396 * 6364 * 166 = 418,343,904 bytes to store it, plus a few more for the array descriptor table. If this is LONG integers, then you are looking at around 1.6Gb of virtual memory!!!

Therefore, it is a safe bet that the Error 7 was because Windows could not allocate enough virtual memory, probably from a lack of disk-space, or your swap file has a size limitation, etc.

If this is just to load three tables, then maybe you really want a 2 dimensional array? One dimension is the row data, the other is the table number.

' Pseudocode
DIM db(%NumDBs, %maxrows) AS <type>
DataFromDB1 = db(1, rownum)
DataFromDB2 = db(2, rownum)
DataFromDB3 = db(3, rownum)

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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[jeroen brouwers]

Ok, you're right, I made a miscalculation. Or to look at it another way: Damned that's gonna be expensive!

Sincerely
Jeroen

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