It seems that malloc calls mmap internally as : so malloc passes NULL as the first argument for mmap as starting address, so the kernel will choose a suitable virtual address for the mapping, which means malloc will not necessarily create a mapping in the heap area(indicated by brk pointer). If this is true, that means there will be a
Tag: virtual-memory
How does Windows/Linux x64 determine the last time a memory page was accessed?
When virtual memory systems decide to evict a memory page out to disk, it’s sometimes mentioned that the last time of access of that memory page is used to help decide which page is evicted. But what mechanism is used to track the last time of access of a memory page? I believe the TLB only stores information on its
Linux page table of the process
I’m reading about the memory paging here and now trying to experiment with it. I wrote a simple assembly program for getting Segmentation Fault and ran in gdb. Here it is: I assemble and link this into a 64-bit ELF static executable. As far as I read each process has its own Page Table which cr3 register points to. Now
Retrieving the memory map of its own process in QNX
In Linux if we look at the /proc/self/maps: I want information like pathname and starting address for Qnx. How can I get that information? My analysis says that there is not /proc/self/maps file in Qnx. Answer We have self file in QNX too !! The address space is represented by a binary file called “as” in every folder in /proc.
How can a process try to access other process’s memory in Linux virtual memory system
Just got confused when I am learning the virtual memory system in Linux. Since each process has its own virtual address space and its own page table translating its virtual address to physical address(am I right?), how can it possibly try to falsely access other process’s memory? There should be no entry in the page table, right? Answer Unless specifically