Mike Richards a écrit :
Hi, I appear to be missing quite a bit of RAM on an x86_64 system. I have 1GB installed, but 'free' only shows 878MB:pokey$ free -m total used free shared buffers cached Mem: 878 571 306 0 52 332 -/+ buffers/cache: 186 691 Swap: 1023 0 1023 I'm used to seeing a little bit of RAM missing with 32bit systems, but 146MB seems a bit much. The part of dmesg that concerns the RAM is shown below. Anyone know what's up here? Is this normal for an x86_64 system? Linux version 2.6.20.11 ([EMAIL PROTECTED]) (gcc version 4.1.2) #1 SMP Thu May 24 18:29:52 GMT 2007 Command line: auto BOOT_IMAGE=2.6.20.11 rw root=801 BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 0000000037fd0000 (usable) BIOS-e820: 0000000037fd0000 - 0000000037fde000 (ACPI data) BIOS-e820: 0000000037fde000 - 0000000038000000 (ACPI NVS) BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved) BIOS-e820: 00000000fee00000 - 00000000fef00000 (reserved) BIOS-e820: 00000000ff780000 - 0000000100000000 (reserved)
I would say your BIOS needs an update or some tweakings. The (usable) parts that it gives to the OS (linux) are : 0000000000000000 - 000000000009fc00 0000000000100000 - 0000000037fd0000 Thats not 1024 MB, but 892 MB Here is the output on a 16 GB x86_64 machine BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 000000007fff0000 (usable) BIOS-e820: 000000007fff0000 - 000000007ffff000 (ACPI data) BIOS-e820: 000000007ffff000 - 0000000080000000 (ACPI NVS) BIOS-e820: 00000000ff780000 - 0000000100000000 (reserved) BIOS-e820: 0000000100000000 - 0000000480000000 (usable) On node 0 totalpages: 2097039 On node 1 totalpages: 2097152 total of 4194078 pages (while exact 16GB should be 4194304 pages) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
