我的系统有 1.25 TB 的 RAM，主板可以看到它，lshw 也可以看到它，但只有 1.0 TB 可用，是否有一个内核参数需要我识别更多内存？
这是华硕主板 RS700-E9，配有 2 个英特尔 XEON Gold 6150 CPU
[root@xtc ~]# lshw -C memory
*-firmware
description: BIOS
vendor: American Megatrends Inc.
physical id: 0
version: 0403
date: 07/04/2017
size: 64KiB
capacity: 16MiB
capabilities: pci apm upgrade shadowing cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer acpi usb biosbootspecification uefi
*-memory
description: System Memory
physical id: 31
slot: System board or motherboard
size: 1280GiB <------------- memory in system
capabilities: ecc
configuration: errordetection=ecc
*-bank:0
description: DIMM DDR4 Synchronous 2400 MHz (0.4 ns)
product: HMAA8GL7MMR4N-UH
vendor: Hynix
physical id: 0
serial: 32BF004A
slot: DIMM_A1
size: 64GiB
width: 64 bits
clock: 2400MHz (0.4ns)
.
.
.
但只能 1 TB
[root@xtc ~]# free -h
total used free shared buff/cache available
Mem: 1.0T 10G 994G 19M 346M 993G
Swap: 4.0G 0B 4.0G
[root@xtc ~]#
[root@xtc ~]# dmidecode -t memory
# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 3.0 present.
Handle 0x0031, DMI type 16, 23 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: Single-bit ECC
Maximum Capacity: 768 GB <---- thats Per CPU
Error Information Handle: Not Provided
Number Of Devices: 6
Handle 0x0033, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0031
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 64 GB
Form Factor: DIMM
Set: None
Locator: DIMM_A1
Bank Locator: NODE 1
Type: DDR4
Type Detail: Synchronous
Speed: 2400 MT/s
Manufacturer: Hynix
Serial Number: 32BF004A
Asset Tag: DIMM_A1_AssetTag
Part Number: HMAA8GL7MMR4N-UH
Rank: 4
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V
Handle 0x0035, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0031
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 64 GB
Form Factor: DIMM
Set: None
Locator: DIMM_A2
Bank Locator: NODE 1
Type: DDR4
Type Detail: Synchronous
Speed: 2666 MT/s
Manufacturer: Micron
Serial Number: 353C140B
Asset Tag: DIMM_A2_AssetTag
Part Number: 72ASS8G72LZ-2G6J1
Rank: 4
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V
Handle 0x0037, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0031
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 64 GB
Form Factor: DIMM
Set: None
Locator: DIMM_B1
Bank Locator: NODE 1
Type: DDR4
Type Detail: Synchronous
Speed: 2400 MT/s
Manufacturer: Hynix
Serial Number: 32BF00A6
Asset Tag: DIMM_B1_AssetTag
Part Number: HMAA8GL7MMR4N-UH
Rank: 4
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V
Handle 0x0039, DMI type 17, 40 bytes
Memory Device
Array Handle: 0x0031
Error Information Handle: Not Provided
Total Width: 72 bits
Data Width: 64 bits
Size: 64 GB
Form Factor: DIMM
Set: None
Locator: DIMM_B2
Bank Locator: NODE 1
Type: DDR4
Type Detail: Synchronous
Speed: 2666 MT/s
Manufacturer: Micron
Serial Number: 353C2294
Asset Tag: DIMM_B2_AssetTag
Part Number: 72ASS8G72LZ-2G6J1
Rank: 4
Configured Memory Speed: 2400 MT/s
Minimum Voltage: 1.2 V
Maximum Voltage: 1.2 V
Configured Voltage: 1.2 V
有任何想法吗 ？？？？
****** 添加 imxi -m 输出
RAM: total: 1005.33 GiB used: 12.41 GiB (1.2%)
Array-1: capacity: 768 GiB slots: 6 EC: Single-bit ECC
Device-1: DIMM_A1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-2: DIMM_A2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-3: DIMM_B1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-4: DIMM_B2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-5: DIMM_C1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-6: DIMM_C2 type: no module installed
Array-2: capacity: 768 GiB slots: 6 EC: Single-bit ECC
Device-1: DIMM_D1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-2: DIMM_D2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-3: DIMM_E1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-4: DIMM_E2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-5: DIMM_F1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-6: DIMM_F2 type: no module installed
Array-3: capacity: 768 GiB slots: 6 EC: Single-bit ECC
Device-1: DIMM_G1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-2: DIMM_G2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-3: DIMM_H1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-4: DIMM_H2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-5: DIMM_J1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-6: DIMM_J2 type: no module installed
Array-4: capacity: 768 GiB slots: 6 EC: Single-bit ECC
Device-1: DIMM_K1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-2: DIMM_K2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-3: DIMM_L1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-4: DIMM_L2 type: DDR4 size: 64 GiB speed: spec: 2666 MT/s
Device-5: DIMM_M1 type: DDR4 size: 64 GiB speed: 2400 MT/s
Device-6: DIMM_M2 type: no module installed
添加 proc/meminfo
# cat /proc/meminfo
MemTotal: 1054167812 kB
MemFree: 1040596332 kB
MemAvailable: 1040131352 kB
Buffers: 1400 kB
Cached: 1305460 kB
SwapCached: 0 kB
Active: 1495260 kB
Inactive: 452332 kB
Active(anon): 643724 kB
Inactive(anon): 33940 kB
Active(file): 851536 kB
Inactive(file): 418392 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 980955128 kB
SwapFree: 980955128 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 638656 kB
Mapped: 166396 kB
Shmem: 36088 kB
Slab: 268216 kB
SReclaimable: 90680 kB
SUnreclaim: 177536 kB
KernelStack: 22864 kB
PageTables: 43764 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 1508039032 kB
Committed_AS: 5051712 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 2269720 kB
VmallocChunk: 34081574908 kB
Percpu: 97280 kB
HardwareCorrupted: 0 kB
AnonHugePages: 221184 kB
CmaTotal: 0 kB
CmaFree: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 320044 kB
DirectMap2M: 9787392 kB
DirectMap1G: 1063256064 kB