On Sad, 2005-08-06 at 20:52 -0700, Nicholas Miell wrote: > Why does overcommit in mode 2 (OVERCOMMIT_NEVER) explicitly force > MAP_NORESERVE mappings to reserve memory? > > My understanding is that MAP_NORESERVE is a way for apps to state that > they are aware that the memory allocated may not exist and that they > might get a SIGSEGV and that's OK with them.
Because a MAP_NORESERVE space that is filled with pages might cause insufficient memory to be left available for another object that is not MAP_NORESERVE. You are right it could be improved but that would require someone writing code that forcibly reclaimed MAP_NORESERVE objects when we were close to out of memory. At the moment nobody has done this, but nothing is stopping someone having a go. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
