Память

1) cat /proc/meminfo
2) dmesg(в самом начале)

# cat /proc/meminfo
MemTotal: 3369728 kB
MemFree: 3192976 kB
Buffers: 40208 kB
Cached: 89128 kB
SwapCached: 0 kB
Active: 90700 kB
Inactive: 49376 kB
HighTotal: 2489792 kB
HighFree: 2384644 kB
LowTotal: 879936 kB
LowFree: 808332 kB
SwapTotal: 4096564 kB
SwapFree: 4096564 kB
Dirty: 44 kB
Writeback: 0 kB
Mapped: 16684 kB
Slab: 22696 kB
CommitLimit: 5781428 kB
Committed_AS: 23412 kB
PageTables: 704 kB
VmallocTotal: 114680 kB
VmallocUsed: 4452 kB
VmallocChunk: 109844 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 4096 kB

]# dmesg |head -n 40
[0x01] lapic_id[0x06] enabled)
Processor #6 15:4 APIC version 20
ACPI: LAPIC_NMI (acpi_id[0x00] high edge lint[0x1])
ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1])
ACPI: IOAPIC (id[0x01] address[0xfec00000] gsi_base[0])
IOAPIC[0]: apic_id 1, version 32, address 0xfec00000, GSI 0-23
ACPI: IOAPIC (id[0x02] address[0xfec81000] gsi_base[24])
IOAPIC[1]: apic_id 2, version 32, address 0xfec81000, GSI 24-47
ACPI: IOAPIC (id[0x03] address[0xfec81400] gsi_base[48])
IOAPIC[2]: apic_id 3, version 32, address 0xfec81400, GSI 48-71
ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 high edge)
ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
ACPI: IRQ0 used by override.
ACPI: IRQ2 used by override.
ACPI: IRQ9 used by override.
Enabling APIC mode: Flat. Using 3 I/O APICs
Using ACPI (MADT) for SMP configuration information
Allocating PCI resources starting at d0000000 (gap: d0000000:10000000)
Built 1 zonelists
Kernel command line: ro root=LABEL=/1
mapped APIC to ffffd000 (fee00000)
mapped IOAPIC to ffffc000 (fec00000)
mapped IOAPIC to ffffb000 (fec81000)
mapped IOAPIC to ffffa000 (fec81400)
Initializing CPU#0
PID hash table entries: 4096 (order: 12, 65536 bytes)
Detected 2800.768 MHz processor.
Using tsc for high-res timesource
Console: colour VGA+ 80x25
Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
Memory: 3368004k/4194304k available (2112k kernel code, 37816k reserved, 413k data, 204k init, 2489792k highmem)
Checking if this processor honours the WP bit even in supervisor mode... Ok.
Calibrating delay using timer specific routine.. 5608.61 BogoMIPS (lpj=11217238)
Mount-cache hash table entries: 512
CPU: After generic identify, caps: bfebfbff 20100000 00000000 00000000 0000641d 00000000 00000000
CPU: After vendor identify, caps: bfebfbff 20100000 00000000 00000000 0000641d 00000000 00000000
monitor/mwait feature present.
using mwait in idle threads.
CPU: Trace cache: 12K uops, L1 D cache: 16K

Извиняюсь, dmesg не с самого начала привел. Вот что на самом деле (из лога извлек):

BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 0000000000099400 (usable)
BIOS-e820: 0000000000099400 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e4000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 00000000cff70000 (usable)
BIOS-e820: 00000000cff70000 - 00000000cff77000 (ACPI data)
BIOS-e820: 00000000cff77000 - 00000000cff80000 (ACPI NVS)
BIOS-e820: 00000000cff80000 - 00000000d0000000 (reserved)
BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
BIOS-e820: 00000000ff800000 - 00000000ffc00000 (reserved)
BIOS-e820: 00000000fffffc00 - 0000000100000000 (reserved)
BIOS-e820: 0000000100000000 - 0000000130000000 (usable)
Warning only 4GB will be used.
Use a PAE enabled kernel.
3200MB HIGHMEM available.
896MB LOWMEM available.
found SMP MP-table at 000f5da0
On node 0 totalpages: 1048576
DMA zone: 4096 pages, LIFO batch:1
Normal zone: 225280 pages, LIFO batch:31
HighMem zone: 819200 pages, LIFO batch:31
DMI present.
Using APIC driver default

Такое ощущение, что вот эти вот 896Мб LOWMEM и исчезли.

Интересная штука. Вот у этой области линейный адрес получился выше 4 Гб: BIOS-e820: 0000000100000000 - 0000000130000000 (usable) Только теперь не совсем понятно как это пофиксить. Можно конечно поставить при компиляции ядра HIGHTMEM64, но может быть это можно исправить какими-нибудь настройками BIOS?