less aggressive contigmalloc ?

[Luigi Rizzo]

On Thu, Aug 23, 2012 at 12:08:40PM -0500, Alan Cox wrote:
...
> >yes i do see that.
> >
> >Maybe less aggressive with M_NOWAIT but still kills processes.
> 
> Are you compiling world with MALLOC_PRODUCTION?  The latest version of 

whatever the default is. But:

> jemalloc uses significantly more memory when debugging options are 
> enabled.  This first came up in a thread titled "10-CURRENT and swap 
> usage" back in June.
> 
> Even at its most aggressive, M_WAITOK, contigmalloc() does not directly 
> kill processes.  If process death coincides with the use of 
> contigmalloc(), then it is simply the result of earlier, successful 
> contigmalloc() calls, or for that matter any other physical memory 
> allocation calls, having depleted the pool of free pages to the point 
> that the page daemon runs and invokes vm_pageout_oom().

does it mean that those previous allocations relied on memory overbooking ?
Is there a way to avoid that, then ?

cheers
luigi