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14

A 32-bit address space means that you have space for 4GB of addresses. Ideally the kernel likes to be able to map all physical memory, all the memory of the current task, and all of its own memory. If physical memory alone takes up all of the available 4GB, that won't work. So physical memory is divided into low memory, which is mapped all the time, and high ...


8

When you examine the contents of /proc/cpuinfo, the flags for the CPU will include "pae".


5

If you have a 64-bit processor, an alternative would be to try a 64-bit kernel. According to this RedHat white paper, a typical server experiences around 1% performance hit, and other tasks suffered a performance hit of 0% - 10%. In addition to having more available memory, enabling PAE means you have an NX bit, which can increase security.


4

The clue likely lies here, from O'Reilly's Understanding the Linux Kernel: "Some real-time operating systems feature preemptive kernels, which means that a process running in Kernel Mode can be interrupted after any instruction, just as it can in User Mode. The Linux kernel is not preemptive, which means that a process can be preempted only while running in ...


4

32-bit processes can only allocate up to 1, 2, 3, or about 4GB, depending on which memory split was chosen when the 32-bit kernel was built. 32-bit processes on a 64-bit kernel can allocate about 4GB. 64-bit processes on a 64-bit x86-64 kernel can allocate up to 128TiB.


3

A 32-bit process can access only about 3GB. (It can be less, depending on the kernel compilation options.) It doesn't matter whether the kernel is a 32-bit or 64-bit one — that only affects the ability to run 64-bit applications. PAE is a way to allow more physical memory but doesn't change the size of the virtual memory seen by each process. That's pretty ...


3

A 32-bit process has a 32-bit address space, by definition: “32-bit” means that memory addresses in the process are 32 bits wide, and if you have 232 distinct addresses you can address at most 232 bytes (4GB). A 32-bit Linux kernel can only execute 32-bit processes. Depending on the kernel compilation options, each process can only allocate 1GB, 2GB or 3GB ...


3

Is it possible that the integrated GPU uses almost 1GB of RAM? Easily. Many integrated GPUs do not have their own dedicated memory, instead using a portion of the system memory carved out by the BIOS. Can I check it somehow? Probably. Check the BIOS settings, and/or the system manual. You should be able to control the memory allocation from ...


2

The kernel sees the physical memory and provides a view to the processes. If you ever wondered how a process can have a 4 GB memory space if your whole machine got only 512 MB of RAM, that's why. Each process has its own virtual memory space. The addresses in that address space are mapped either to physical pages or to swap space. If to swap space, they'll ...


2

Well, I do not expect a concise answer than the one available from here. What I understand about 32-bit OS is, the address is expressed in 32 bits, so at most the OS could use 2^32 = 4GB memory space The most that the process can address is 4GB. You are potentially confusing memory with address space. A process can have more memory than address space. ...


2

As far as I can see, since Mint is based on Ubuntu, it will support whatever the standard Ubuntu kernel supports. Thus Mint 14 is based on Ubuntu 12.10's kernel, which has PAE by default. Also, PAE has nothing to do with the desktop environment.


2

pae will be in the "flags" section of the output of 'cat /proc/cpuinfo' PAE is Physical Address Extension. It's a way of addressing large amounts of memory. Here are a couple of links about it: http://serverfault.com/questions/85980/what-processors-do-do-not-support-pae ...


1

No it has to do with RAM. Check out the Wikipedia page on PAE (Physical Address Extension). excerpt In computing, Physical Address Extension (PAE) is a feature to allow 32-bit x86 central processing units (CPUs) to access a physical address space (including random access memory and memory mapped devices) larger than 4 gigabytes. I also found out why ...



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