Still, in this case this shouldn't be a problem. A file causing the error has 599 MB (the error says TIC memory limit exceeded 799 MB). I can load slightly smaller file which has 572 MB. During the backtest Zorro uses only 781 MB of memory, so there's still lot of potential space.

A side note: Zorro is almost 5 years old. As I see it the market generated data volume has almost doubled since that time. It will probably grow in the future too. Something has to be done to keep up with this development.

The Zorro memory limit is 3 GB per instance, and 1.2 GB per single allocation, due to the 32 bit limit.

So why is it possible to perform backtest on 572 MB history file with Zorro taking up 781 MB of memory and 599 MB history file gives an error? It should be still in the limit, shouldn't it? And is there any chance there will be 64 bit version in the future?

599 MB is no problem. The limit is 3000 MB. So there must be a lot more allocated when you get an error message. You can see the current memory consumption in the Windows Task Manager.

A 64 bit version is possible, but would require a different compiler. The lite-C compiler generates 32 bit code.

It must be a bug then. Maybe again an error in memory size computation? See the screenshots with minimal example and file and memory information:

This runs OK:


This gives an error every time:

I see no screenshots, but a bug is always possible - however in this case you probably had to ask Bill Gates to fix it. Memory allocation is done by Windows, not by Zorro.

There's also another possibility: Memory is still free, but not contiguous, so huge arrays can not be allocated. That's the reason for the 1200 MB allocation limit. The limit can be smaller when your memory is heavily fragmented. I have not experienced any problems so far with large tick data files, but maybe I was just lucky.

That's weird, I can see them in different browsers. What about these links?

https://s29.postimg.org/h9tk578af/limit_ok.png
https://s29.postimg.org/qlv1ww0vb/limit_exceeded.png

With highest probability the memory not being contiguous is not the issue here. It happens every time, even after a fresh system start.

What I meant is whether it cannot be related to the issue described in the beginning of the thread - to quote you:



So you are indeed able to backtest on history data files larger than 600 MB with Zorro 1.52?

I can see the screenshots now, but they contain no info about the system memory allocation. There's a performance tab in the task manager where you can see that.

I can start your example script as often as I want and get no memory problem. However the 2015 EURUSD.t1 history is less than 600 MB. I have no >600 MB t1 history at this point - must download it first. If you're tight on memory, you can save some with the LEAN flag.

True. If I check the largest free block of memory available to Zorro it has 2 GB atm. Yet the script crashes with Error 060: TIC memory limit exceeded (799 MB). I uploaded the .t1 file if you want to give it a try: https://we.tl/aLaTBOnxeq

Thanks! I can confirm the problem with your .t1 file. It happens on my PC too and looks like a bad allocation order when Zorro loads the historical data - as if a new area is allocated before the old one is freed. This exceeds the limit every time. This can be probably fixed and we'll do that with high priority before the next release.