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Hello again, This time I am wondering if it is possible, and if so how to go about configureing slackwares kernel to recognize 8GB of RAM. Can this be done ...
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    More RAM please


    Hello again,

    This time I am wondering if it is possible, and if so how to go about configureing slackwares kernel to recognize 8GB of RAM. Can this be done in normal 32bit or is that just not an option.

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    Linux Guru coopstah13's Avatar
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    Thanks for the link Coopstah.

    So let me see if I understand this correctly. If I have Himem enabled (which I'm not exactly sure how to go about doing that). Than my OS can use up to 64GB of RAM. But it won't mater if I am running 32bit architecture.

    So to use 8 GB I need to switch to a 64bit distro of slackware like slamd64.

    Am I getting this right or was there another solution in there I missed. I tried to read all the comments but they just appear to be people bickering about how memmory addresses are writen to page files

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    PAE - Wikipedia

    The x86 processor hardware is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits. This increases maximum physical memory size from 4 Gib to 64 GiB.
    The Linux kernel includes full PAE support starting with version 2.6,[3] enabling access of up to 64 GB of memory on 32-bit machines. A PAE-enabled Linux-kernel requires that the CPU also support PAE. As of 2008[update], many common Linux distributions come with a PAE-enabled kernel as the distribution-specific default.

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    Linux Engineer Freston's Avatar
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    You will want to recompile your kernel, as it does not utilize that much RAM by default.

    I thought alien's wiki was a good resource.
    Can't tell an OS by it's GUI

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    please forgive my ignorance, re-compiling a kernel is a little bit above my current level of understanding.

    This guide that Freston linked to appears to be a tutorial on how to build a 2.6 kernel.

    I am very satisfied (like I would know the differnence anyways) with the 2.6 kernel that already comes with 12.1 or even 12.2 (I'm looking into upgradeing to that because I want compiz and I can't seem to get it to work, since it comes with 12.2 i'm assuming it works)

    All I want to do is edit the existing kernel to make it see 8 Gigs of ram.

    Am I just not understanding this right, is that not possible?

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    It is possible but if I'm completely honest with you it's a waste of time. The process used to address extended memory uses a lot of memory itself as 32-bit processors run out of addresses after 3GB of RAM. Basically it becomes self defeating.

    As an example, if you have 3GB of RAM and you install an extra 1GB of RAM you will have 4GB of physical RAM but only address 3.2GB in your system. That's 800MB in the trashbin through PAE.

    A much more sensible solution is to switch to a 64-bit operating system. Yeah you can use the PAE workaround mentioned above but in my humble opinion it's a waste. You paid for it, might as well use it

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    well thank you sir that is the kind of honest answer I have been looking for. I have seen two slackware 64 distros out there, slamd64, and bluewhite64. Can you make a solid recomondation for any of those two or perhaps a differnt distro you are familiar with. I would really appreciate it

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    Wellllll, I've used a lot of good distros in my time and a lot of bad ones too. I'm currently on the Ubuntu wagon despite saying I never would. It's a good solid distro, but if you're one for the Slack kind of approach you might feel like it's spoonfeeding you or that it's too 'automatic'. Debian is always a good choice as you can have as much or as little as you want. I used Mandriva and SUSE for a year or two each and if I was to recommend one I'd recommend SUSE.

    Good luck getting sorted anyway, if I can be of any help I will

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    As an example, if you have 3GB of RAM and you install an extra 1GB of RAM you will have 4GB of physical RAM but only address 3.2GB in your system. That's 800MB in the trashbin through PAE.
    No - when a PAE-enabled CPU is used in conjunction with a PAE-enabled kernel, up to 64GB of RAM can be used. Note the part where the number of memory address lines is increased from 32 to 36 bits. *Applications* still use 32 bit addresses, so any single application will still be limited to 4GB, but the total RAM is available to the kernel/OS.

    The x86 processor hardware is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits. This increases maximum physical memory size from 4 GiB to 64 GiB. The 32-bit size of virtual address is not changed, so regular application software continues to use instructions with 32-bit addresses and (in a flat memory model) is limited to 4 gigabytes (GiB). The operating system uses page tables to map this 4 GiB address space onto the 64 GiB of total memory, and the map is usually different for each process. In this way the extra memory is useful even though no single regular application can access it all simultaneously.

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