Messages in this thread | | | Date | Fri, 17 Mar 2000 16:31:03 +0100 | From | Jamie Lokier <> | Subject | Re: Overcommitable memory?? |
| |
Andreas Bombe wrote: > > Because it *IS* overcommitment of memory. You can have two processes, each > > with their 200Mb of data, in a machine with 256Mb RAM+swap, quite happily > > - until they start writing to it, at which point you discover you have > > overcommitted your memory, and things go wrong. > > He means avoiding overcommit by counting vm requirements but without > actually copying COW pages (denying a COW allocation if it could not > be faulted in at a later time). Resulting in vast areas of unused > RAM.
Just like the mythical internet Quality of Service, you can always find a use for that non-dedicated capacity... The RAM will never be unused. It will used by MAP_NORESERVE mappings, processes that specifically said "I don't mind being overcommitted", and fs cache.
have a nice day, -- Jamie
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |