Applications with dynamic input and dynamic memory usage have some issues with the current overcommitting kernel. A high memory usage situation eventually results in that a process is killed by the OOM killer. This is especially evident in swapless embedded systems with limited memory and no swap available.
Some kind of notification to the application that the available memory is scarce and let the application free up some memory (e.g., by flushing caches), could be used to improve the situation and avoid the OOM killer. I am currently not aware of any general solution to this problem, but I have found some approaches that might (or might not) work: o Turn off overcommit. Results in a waste of memory. o Nokia uses a lowmem security module to signal on predetermined thresholds. Currently available in the -omap tree. But this requires manual tuning of the thresholds. http://www.linuxjournal.com/article/8502 o Using madvise() with MADV_FREE to get the kernel to free mmaped memory, typically application caches, when the kernel needs the memory. o A OOM handler that the application registers with the kernel, and that the kernel executes before the OOM-killer steps in. Does it exist any other solutions to this problem? Daniel - 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/
