Increase stack size in QT

Question

I know that I can use these flags in .pro to increse the size of the stack and the heap in my c++ project in QT. But in linux it has no effect and I still have the stack size problem. How can I solve that in linux or is there an another solution?

QMAKE_CXXFLAGS += -Wl,--stack,100000000
QMAKE_CXXFLAGS += -Wl,--heap,100000000

I think you'd be far better off spending some time trying to find the underlying cause of your stack size problem. — G.M., Mar 05 '18 at 10:16
thanks, but this is obvious. I have a big array with about ten millions elements. — morteza ali ahmadi, Mar 05 '18 at 10:19
thanks but I can't because I need a buffer array and there is some problems by converting a vector to array. — morteza ali ahmadi, Mar 05 '18 at 10:25
Morteza _An array with 10M elements_ .. if your app crashes aren't you going to loose any updates? isn't it reliable to store elements in DB? — Mohammad Kanan, Mar 05 '18 at 10:25
thanks, I read these 10 millions elements from DB and I want to use them in my program. — morteza ali ahmadi, Mar 05 '18 at 10:32
Probably, this is a mitigation by code [increase Linux stack with c++](https://stackoverflow.com/questions/2279052/increase-stack-size-in-linux-with-setrlimit) — Mohammad Kanan, Mar 05 '18 at 11:12

dtech · Answer 1 · 2018-03-05T11:28:59.793

You are going about it all wrong. The stack is not about storing program data, it is about storing program state.

Large amounts of data should be on the heap, the stack is only what keeps the program code together, it is the backbone of the application, not its data base.

Try this instead:

QVector<YourType> data(100000000);

Provided the system can allocate enough memory, you now can use that data with the standard array [] operator.

Keep in mind that 100m ints are already over 380 mb. Even if you increase the stack size, nobody uses 380 mb stacks, the typical stack size is usually no more than a few megabytes, and that is good enough to work for immensely large applications. If your data type is larger, it will require even more continuous memory, so depending on your system and compiler, it is entirely possible that such an allocation cannot be made even on the heap.

score 0 · Answer 2 · answered Oct 11 '20 at 01:34

0

You cannot change stack size by passing flags to gcc in Linux. You should use the command "ulimit -s newsize" to change it.

answered Oct 11 '20 at 01:34

William

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Increase stack size in QT

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