On Mon, Mar 11, 2019 at 05:11:25PM -0400, Joel Fernandes wrote: > But the point is that a transient temporary memory spike should not be a > signal to kill _any_ process. The reaction to kill shouldn't be so > spontaneous that unwanted tasks are killed because the system went into > panic mode. It should be averaged out which I believe is what PSI does. In my patch from the first email, I implemented the decision to kill a process at the same time that the existing kernel OOM killer decides to kill a process. If the kernel's OOM killer were susceptible to killing processes due to transient memory spikes, then I think there would have been several complaints about this behavior regardless of which userspace or architecture is in use. I think the existing OOM killer has this done right. The decision to kill a process occurs after the page allocator has tried _very_ hard to satisfy a page allocation via alternative means, such as utilizing compaction, flushing file-backed pages to disk via kswapd, and direct reclaim. Once all of those means have failed, it is quite reasonable to kill a process to free memory. Trying to wait out the memory starvation at this point would be futile. Thanks, Sultan
