Yakkety 服务器使用通用内核版本。它是 4.8.0 Linux 内核。
在英特尔 KNL 处理器上运行时，我看不到 256 个以上的核心。
user@ubuntu02:~$ grep processor /proc/cpuinfo | wc -l
256
dmidecode 显示实际核心数
user@ubuntu02:~$ sudo dmidecode -t 4
[sudo] password for user:
# dmidecode 3.0
Getting SMBIOS data from sysfs.
SMBIOS 3.0 present.
Handle 0x001B, DMI type 4, 48 bytes
Processor Information
Socket Designation: CPU0
Type: Central Processor
Family: Xeon
Manufacturer: Intel(R) Corporation
ID: 71 06 05 00 FF FB EB BF
Signature: Type 0, Family 6, Model 87, Stepping 1
Flags:
FPU (Floating-point unit on-chip)
VME (Virtual mode extension)
DE (Debugging extension)
PSE (Page size extension)
TSC (Time stamp counter)
MSR (Model specific registers)
PAE (Physical address extension)
MCE (Machine check exception)
CX8 (CMPXCHG8 instruction supported)
APIC (On-chip APIC hardware supported)
SEP (Fast system call)
MTRR (Memory type range registers)
PGE (Page global enable)
MCA (Machine check architecture)
CMOV (Conditional move instruction supported)
PAT (Page attribute table)
PSE-36 (36-bit page size extension)
CLFSH (CLFLUSH instruction supported)
DS (Debug store)
ACPI (ACPI supported)
MMX (MMX technology supported)
FXSR (FXSAVE and FXSTOR instructions supported)
SSE (Streaming SIMD extensions)
SSE2 (Streaming SIMD extensions 2)
SS (Self-snoop)
HTT (Multi-threading)
TM (Thermal monitor supported)
PBE (Pending break enabled)
Version: Intel(R) Xeon Phi(TM) Processor 000A @ 1.40GHz
Voltage: 0.9 V
External Clock: 100 MHz
Max Speed: 4000 MHz
Current Speed: 1400 MHz
Status: Populated, Enabled
Upgrade: <OUT OF SPEC>
L1 Cache Handle: 0x0019
L2 Cache Handle: 0x001A
L3 Cache Handle: Not Provided
Serial Number: To Be Filled By O.E.M.
Asset Tag: To Be Filled By O.E.M.
Part Number: To Be Filled By O.E.M.
Core Count: 68
Core Enabled: 68
Thread Count: 272
Characteristics:
64-bit capable
Multi-Core
Hardware Thread
Execute Protection
Power/Performance Control
是否有可能在不重新编译内核的情况下启用所有 272 个核心？
user@ubuntu02:~$ grep CONFIG_NR_CPUS /boot/config-4.8.0-32-generic
CONFIG_NR_CPUS=256
我认为 Ubuntu Server 内核版本应该已经为此做好了准备。
答案1
Yakkety 内核中的 CPU 数量最近已增加到 512 个，并将在内核版本 Ubuntu-4.8.0-34.35 中实现：
commit 4cc43dc6b3bf9ea5b9ed6d91af47dbe137a71cd9
Author: Luis Henriques <[email protected]>
Date: Thu Dec 8 10:36:14 2016 +0000
UBUNTU: [Config] Increase the NR_CPUS to 512 for amd64 to support systems with a large number of cores.
BugLink: http://bugs.launchpad.net/bugs/1579205
Signed-off-by: Luis Henriques <[email protected]>
Acked-by: Colin Ian King <[email protected]>
Acked-by: Tim Gardner <[email protected]>
因此，如果您没有运行该内核，请更新，然后您应该会得到此修复。