c - numa_alloc_onnode() allocates memory more then it can? -

c - numa_alloc_onnode() allocates memory more then it can? -

i tried utilize numa_alloc_onnode() allocate 40gb of memory on 32gb node running below code. not study errors.

a = (int *) numa_alloc_local (sizeof(int) * gb_8 * 5); if (a == null) printf("a error\n"); ( = 0; <gb_8*5; i++ ) a[i] = (int)i; printf("a done\n");

this specification of machine. http://i.stack.imgur.com/bm2gr.png

can please help explain?

until seek store in memory, it's vapor, imaginary... virtual even!

the scheme say, sure! can have much in name... it's 'on paper' until utilize it.

if seek store in 40+gb of memory, you'd encounter errors... depends on size of swap space @ point.

the first 3 google hits overcommit:

https://www.kernel.org/doc/documentation/vm/overcommit-accounting http://www.win.tue.nl/~aeb/linux/lk/lk-9.html http://searchservervirtualization.techtarget.com/definition/memory-overcommit

just remember until store there, it's imaginary anyways.

c memory malloc numa