On Wed, Sep 21, 2016 at 4:41 PM, Jeroen Demeyer <jdeme...@cage.ugent.be> wrote:
I tested this with a small stand-alone C program: the flags > PROT_NONE | MAP_PRIVATE | MAP_ANONYMOUS > allow to allocate huge amounts of virtual memory, even with overcommit=2. I also tried this. And I alsoo found that the memory does count against the commit limit once mprotect() is called with PROT_READ | PROT_WRITE. Also, with PROT_NONE I tried allocating 100 TB (with PROT_NONE, again) to 200 different processes at the same time, and I couldn't even notice any effect of this in /proc/meminfo. I haven't actually found this behavior documented anywhere, and it would be good to know that it works similarly on OS X. There is still a small cost: the memory does count against the process as far as ulimit -v is concerned. But that doesn't seem like much of an issue to me. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
