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Re: change to gcc from lcc
2008/11/20 Michael Matz <matz@suse.de>:
> Hi,
>
> On Wed, 19 Nov 2008, H.J. Lu wrote:
>
>> On Wed, Nov 19, 2008 at 7:18 PM, Nicholas Nethercote
>> <njn@csse.unimelb.edu.au> wrote:
>> > On Tue, 18 Nov 2008, H.J. Lu wrote:
>> >
>> >>> I used malloc to create my arrays instead of creating the in the stack.
>> >>> My program is working now but it is very slow.
>> >>>
>> >>> I use two-dimensional arrays. The way I access element (i,j) is:
>> >>> array_name[i*row_length+j]
>> >>>
>> >>> The server that I use has 16GB ram. The ulimit -a command gives the
>> >>> following output:
>> >>> time(seconds) unlimited
>> >>> file(blocks) unlimited
>> >>> data(kbytes) unlimited
>> >>> stack(kbytes) 8192
>> >>
>> >> ^^^^^^^^^^^^^^^^^^^^^^^^
>> >>
>> >> That limits stack to 8MB. Please change it to 1GB.
>> >
>> > Why?
>> >
>>
>> int buffer1[250][1000000];
>>
>> takes close to 1GB on stack.
>
> Read the lines you quoted carefully again.
>
>
> Ciao,
> Michael.
>
Can you please talk in a more understandable way? I also think that 4
* 250 * 1000000 is close to 1073741824 which is 1 Gb. And automatic
variables are allocated in stack (which is 8Mb here) instead of data
segment.
Alexey