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How to use all 32G of ram on a quad core

By happygdk
Aug 1, 2009
  1. Running a stand alone single application on a processor, my Intel quad core (core2 Extreme) seems to see only 16G of ram. How do I make the program utilize all 32G of ram (8x4G ram sticks).
     
  2. red1776

    red1776 Omnipotent Ruler of the Universe Posts: 5,219   +157

    ??????, uhhhh would you list your detailed specs please?
     
  3. happygdk

    happygdk TS Rookie Topic Starter

    Oh, sorry. OS is fedora core 8 (2.6.25.9-40.fc8) and dual quad cores. Here's cpuinfo on one of the processors:

    processor : 0
    vendor_id : GenuineIntel
    cpu family : 6
    model : 23
    model name : Intel(R) Core(TM)2 Extreme CPU X9650 @ 3.00GHz
    stepping : 6
    cpu MHz : 2992.481
    cache size : 6144 KB
    physical id : 0
    siblings : 4
    core id : 0
    cpu cores : 4
    fpu : yes
    fpu_exception : yes
    cpuid level : 10
    wp : yes
    flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall lm constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm
    bogomips : 5988.27
    clflush size : 64
    cache_alignment : 64
    address sizes : 36 bits physical, 48 bits virtual
    -----------------------------------------------------------
    "free" gives me:

    total used free shared buffers cached
    Mem: 3997120 1229044 2768076 0 7868 287884
    -/+ buffers/cache: 933292 3063828
    Swap: 4194296 1110236 3084060
    -----------------------------------------------------------
    "meminfo" gives me:

    MemTotal: 3997120 kB
    MemFree: 2768200 kB
    Buffers: 7896 kB
    Cached: 287900 kB
    SwapCached: 554916 kB
    Active: 807904 kB
    Inactive: 153888 kB
    SwapTotal: 4194296 kB
    SwapFree: 3084060 kB
    Dirty: 36 kB
    Writeback: 0 kB
    AnonPages: 487628 kB
    Mapped: 133840 kB
    Slab: 32692 kB
    SReclaimable: 8464 kB
    SUnreclaim: 24228 kB
    PageTables: 34220 kB
    NFS_Unstable: 2044 kB
    Bounce: 0 kB
    CommitLimit: 6192856 kB
    Committed_AS: 1946128 kB
    VmallocTotal: 34359738367 kB
    VmallocUsed: 315612 kB
    VmallocChunk: 34359422687 kB
    HugePages_Total: 0
    HugePages_Free: 0
    HugePages_Rsvd: 0
    HugePages_Surp: 0
    Hugepagesize: 2048 kB

    What other information would be helpful? Thanks.
     
  4. red1776

    red1776 Omnipotent Ruler of the Universe Posts: 5,219   +157

    what motherboard are you using? im not understanding your question i guess, what type of system is this that has 32Gb of ram and 8 dimms?
     
  5. happygdk

    happygdk TS Rookie Topic Starter

    dual xeon quad w/ 32G of ram

    It's a dual quad machine, designed to run multiple independent processes each using 4G of RAM, but I'd like to run an application on a single processor but using all 32G of RAM.

    The info I gave earlier is for the desktop I'm using, not the dual quad cluster machine I'm trying to use. Sorry.

    dual quad Xeon E5440, with RHEL5.3 (2.6.18-128.el5)

    "lshal" give me:
    udi = '/org/freedesktop/Hal/devices/pci_1002_515e'
    info.udi = '/org/freedesktop/Hal/devices/pci_1002_515e' (string)
    linux.subsystem = 'pci' (string)
    linux.hotplug_type = 1 (0x1) (int)
    pci.subsys_product = 'Unknown (0x81de)' (string)
    pci.subsys_vendor = 'ASUSTeK Computer Inc.' (string)
    info.product = 'ES1000' (string)
    pci.product = 'ES1000' (string)
    info.vendor = 'ATI Technologies Inc' (string)
    ------------------------------------------------------------

    cpuinfo:
    processor : 0
    vendor_id : GenuineIntel
    cpu family : 6
    model : 23
    model name : Intel(R) Xeon(R) CPU E5440 @ 2.83GHz
    stepping : 10
    cpu MHz : 2826.325
    cache size : 6144 KB
    physical id : 0
    siblings : 4
    core id : 0
    cpu cores : 4
    apicid : 0
    fpu : yes
    fpu_exception : yes
    cpuid level : 13
    wp : yes
    flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni tm2 lahf_lm
    bogomips : 5654.74
    clflush size : 64
    cache_alignment : 64
    address sizes : 38 bits physical, 48 bits virtual
    -----------------------
    "free"
    total used free shared buffers cached
    Mem: 32959152 12105232 20853920 0 183484 11766756
    -/+ buffers/cache: 154992 32804160
    Swap: 16948564 29124 16919440
    --------------------------------

    "meminfo"
    MemTotal: 32959152 kB
    MemFree: 20850516 kB
    Buffers: 183500 kB
    Cached: 11766748 kB
    SwapCached: 7316 kB
    Active: 6471232 kB
    Inactive: 5506036 kB
    HighTotal: 0 kB
    HighFree: 0 kB
    LowTotal: 32959152 kB
    LowFree: 20850516 kB
    SwapTotal: 16948564 kB
    SwapFree: 16919440 kB
    Dirty: 12 kB
    Writeback: 0 kB
    AnonPages: 25952 kB
    Mapped: 9104 kB
    Slab: 89860 kB
    PageTables: 5696 kB
    NFS_Unstable: 0 kB
    Bounce: 0 kB
    CommitLimit: 33428140 kB
    Committed_AS: 142700 kB
    VmallocTotal: 34359738367 kB
    VmallocUsed: 270884 kB
    VmallocChunk: 34359467043 kB
    HugePages_Total: 0
    HugePages_Free: 0
    HugePages_Rsvd: 0
    Hugepagesize: 2048 kB
     
  6. red1776

    red1776 Omnipotent Ruler of the Universe Posts: 5,219   +157

    If i understand the dual xeon system correctly, (and i have only read about them mind you) although the processing capability can be combined to a single tasks, each has its own set of dedicated dimms and as such memory allocation. i am curious though, what "single application" are you running that you want 32 GB of ram for? anyway i am chiming in because you have gotten no other response as of yet, hopefully someone more knowledgeable abot dual xeon setups will be around here shortly :)
     
  7. happygdk

    happygdk TS Rookie Topic Starter

    Thanks for your reply. Ordinarily, the dual quad machines are part of a cluster to which lots of computational jobs are sent, and in my case, all independent so don't need parallel processing. But what I am trying to do is using only a single processor of a dual quad machine, I want to be able to use all 32G. This can be done using our scheduler but for various reasons I need to test on a single machine. It's just basically "combinatorial" calculation, like having thousands of atoms and their interactions with each other which is astronomical.

    Yes, a clever program wouldn't require much memory but this one does and I'm not about to rewrite it since it's the work of years. :)

    Thanks.
     
  8. red1776

    red1776 Omnipotent Ruler of the Universe Posts: 5,219   +157

    that's really interesting, is this your program? anywhere one might find out more about it?
     
  9. strategic

    strategic TechSpot Paladin Posts: 1,020

    Not sure if I can be much help, but have you tried looking in the Bios sttings? I don't think you can use all 32GB on one processor, I don't think 1 processor can handle that much ram. :suspiciou
     
  10. happygdk

    happygdk TS Rookie Topic Starter

    Is there a way to check the bios remote?

    red1776,
    if you describe your email, I'd be happy to send more info. I'm at a university.

    Thanks.
     
  11. dmill89

    dmill89 TS Guru Posts: 475

    If I understand this correctly there is no way to use all 32Gb. It has nothing to do with the CPU not being able to handle it but with how a dual processor board is set up. most dual CPU boards have dedicated ram slots for each CPU if you have 4 ram slots for CPU1 and 4 slots for CPU 2 you can only use the ram in the 4 slots for CPU1 since the slots are connected directly to the intended CPU (slots for CPU1 connected to CPU1 slots for CPU2 connected to CPU2) and do not have any interconnects allowing them to be used with the other CPU (This is more efficient if yo do run 2 CPUs sence they are not fighting over the same ram).
     
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