Re: TASK_UNMAPPED_BASE & stack location

Rik van Riel
2003-04-26T14:25:05Z

On Fri, 25 Apr 2003, Martin J. Bligh wrote:

> Is there any good reason we can't remove TASK_UNMAPPED_BASE, and just shove
> libraries directly above the program text? Red Hat seems to have patches to
> dynamically tune it on a per-processes basis anyway ...

What could be done is leave the stack where it is, but have
malloc() space and mmap() space grow towards each other:

0 3G
| |prog | malloc --> <-- mmap | stack |

The stack will get the stack size ulimit size and the space
between where malloc and mmap start should be about 2.7 GB.

That 2.7 GB will of course by divided between malloc and mmap,
but the division will be done dynamically based on whoever
needs the space. Much better than the current static 1:1.7
division...