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Re: maximum array size?
Ok, thanks a lot for your help.
Anna
----- Original Message -----
From: "John S. Fine" <johnsfine@verizon.net>
Date: Thursday, April 15, 2010 6:30 pm
Subject: Re: maximum array size?
> Integers in x86_64 are 32 bit. So in your chain of multiplying
> you need
> to multiply by something of type std::size_t before the running
> value
> goes over two billion.
>
> As it is now, you get overflow in the integer multiply so the case
> that
> seems to work is actually reserving far less memory than you think
> you
> are requesting.
>
> Once you get rid of the integer overflow, you should see that the
> amount
> you can reserve is limited by swap size plus large part of ram, so
> if
> you really want something that big, you'll need a lot more swap space.
>
> Anna Sidera wrote:
> > inp_par_a=10000 and inp_par_b=10000. For inp_par_c=60 the
> program works. For inp_par_c=40 or inp_par_c=80 I get segmentation
> fault.>
> > I just calculated the memory the array needs and it is more than
> the available 10GB ram + 3GB swap in the system even for inp_par_c=40.
> >
> >
> >
> >
> >
>
>