//从修改的 /etc/default/grub 生成 /boot/grub2/grub.cfg 配置 //如果是uefi引导，则是 /boot/efi/EFI/redhat/grub.cfg sudo grub2-mkconfig -o /boot/grub2/grub.cfg #limit the journald log to 500M sed -i 's/^#SystemMaxUse=$/SystemMaxUse=500M/g' /etc/systemd/journald.conf #重启系统 #sudo reboot ## 选择不同的kernel启动 #sudo grep "menuentry " /boot/grub2/grub.cfg | grep -n menu ##grub认的index从0开始数的 #sudo grub2-reboot 0; sudo reboot or #grub2-set-default "CentOS Linux (3.10.0-1160.66.1.el7.x86_64) 7 (Core)" ; sudo reboot
GRUB 2 reads its configuration from the /boot/grub2/grub.cfg file on traditional BIOS-based machines and from the /boot/efi/EFI/redhat/grub.cfg file on UEFI machines. This file contains menu information.
The GRUB 2 configuration file, grub.cfg, is generated during installation, or by invoking the /usr/sbin/grub2-mkconfig utility, and is automatically updated by grubby each time a new kernel is installed. When regenerated manually using grub2-mkconfig, the file is generated according to the template files located in /etc/grub.d/, and custom settings in the /etc/default/grub file. Edits of grub.cfg will be lost any time grub2-mkconfig is used to regenerate the file, so care must be taken to reflect any manual changes in /etc/default/grub as well.
/* * This variable becomes 1 if iommu=pt is passed on the kernel command line. * If this variable is 1, IOMMU implementations do no DMA translation for * devices and allow every device to access to whole physical memory. This is * useful if a user wants to use an IOMMU only for KVM device assignment to * guests and not for driver dma translation. */
#dmidecode -t memory # dmidecode 3.2 Getting SMBIOS data from sysfs. SMBIOS 3.2.1 present. # SMBIOS implementations newer than version 3.2.0 are not # fully supported by this version of dmidecode.
Handle 0x0033, DMI type 16, 23 bytes Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: Multi-bit ECC Maximum Capacity: 2 TB //最大支持2T Error Information Handle: 0x0032 Number Of Devices: 32 //32个插槽 Handle 0x0041, DMI type 17, 84 bytes Memory Device Array Handle: 0x0033 Error Information Handle: 0x0040 Total Width: 72 bits Data Width: 64 bits Size: 32 GB Form Factor: DIMM Set: None Locator: CPU0_DIMMA0 Bank Locator: P0 CHANNEL A Type: DDR4 Type Detail: Synchronous Registered (Buffered) Speed: 2933 MT/s //内存最大频率 Manufacturer: SK Hynix Serial Number: 220F9EC0 Asset Tag: Not Specified Part Number: HMAA4GR7AJR8N-WM Rank: 2 Configured Memory Speed: 2400 MT/s //内存实际运行速度--比如内存条数插太多会给内存降频 Minimum Voltage: 1.2 V Maximum Voltage: 1.2 V Configured Voltage: 1.2 V Memory Technology: DRAM Memory Operating Mode Capability: Volatile memory Module Manufacturer ID: Bank 1, Hex 0xAD Non-Volatile Size: None Volatile Size: 32 GB #lshw *-bank:19 description: DIMM DDR4 Synchronous Registered (Buffered) 2933 MHz (0.3 ns) //内存最大频率 product: HMAA4GR7AJR8N-WM vendor: SK Hynix physical id: 13 serial: 220F9F63 slot: CPU1_DIMMB0 size: 32GiB //实际所插内存大小 width: 64 bits clock: 2933MHz (0.3ns)
./Linux/mlc Intel(R) Memory Latency Checker - v3.9 Measuring idle latencies (in ns)... Numa node Numa node 0 1 0 77.9 143.2 1 144.4 78.4
Measuring Peak Injection Memory Bandwidths for the system Bandwidths are in MB/sec (1 MB/sec = 1,000,000 Bytes/sec) Using all the threads from each core if Hyper-threading is enabled Using traffic with the following read-write ratios ALL Reads : 225097.1 3:1 Reads-Writes : 212457.8 2:1 Reads-Writes : 210628.1 1:1 Reads-Writes : 199315.4 Stream-triad like: 190341.4
Measuring Memory Bandwidths between nodes within system Bandwidths are in MB/sec (1 MB/sec = 1,000,000 Bytes/sec) Using all the threads from each core if Hyper-threading is enabled Using Read-only traffic type Numa node Numa node 0 1 0 113139.4 50923.4 1 50916.6 113249.2
Measuring Loaded Latencies for the system Using all the threads from each core if Hyper-threading is enabled Using Read-only traffic type Inject Latency Bandwidth Delay (ns) MB/sec ========================== 00000 261.50 225452.5 00002 263.79 225291.6 00008 269.02 225184.1 00015 261.96 225757.6 00050 260.56 226013.2 00100 264.27 225660.1 00200 130.61 195882.4 00300 102.65 133820.1 00400 95.04 101353.2 00500 91.56 81585.9 00700 87.94 58819.1 01000 85.54 41551.3 01300 84.70 32213.6 01700 83.14 24872.5 02500 81.74 17194.3 03500 81.14 12524.2 05000 80.74 9013.2 09000 80.09 5370.0 20000 78.92 2867.2
Measuring cache-to-cache transfer latency (in ns)... Local Socket L2->L2 HIT latency 51.6 Local Socket L2->L2 HITM latency 51.7 Remote Socket L2->L2 HITM latency (data address homed in writer socket) Reader Numa Node Writer Numa Node 0 1 0 - 111.3 1 111.1 - Remote Socket L2->L2 HITM latency (data address homed in reader socket) Reader Numa Node Writer Numa Node 0 1 0 - 175.8 1 176.7 -
[root@numaopen.cloud.et93 /home/admin] #lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 104 On-line CPU(s) list: 0-103 Thread(s) per core: 2 Core(s) per socket: 26 Socket(s): 2 NUMA node(s): 2 Vendor ID: GenuineIntel CPU family: 6 Model: 85 Model name: Intel(R) Xeon(R) Platinum 8269CY CPU @ 2.50GHz Stepping: 7 CPU MHz: 3199.902 CPU max MHz: 3800.0000 CPU min MHz: 1200.0000 BogoMIPS: 4998.89 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 1024K L3 cache: 36608K NUMA node0 CPU(s): 0-25,52-77 NUMA node1 CPU(s): 26-51,78-103
#dmidecode -t memory Handle 0x003C, DMI type 17, 40 bytes Memory Device Array Handle: 0x0026 Error Information Handle: Not Provided Total Width: 72 bits Data Width: 64 bits Size: 32 GB Form Factor: DIMM Set: None Locator: CPU1_DIMM_E1 Bank Locator: NODE 2 Type: DDR4 Type Detail: Synchronous Speed: 2666 MHz Manufacturer: Samsung Serial Number: 14998029 Asset Tag: CPU1_DIMM_E1_AssetTag Part Number: M393A4K40BB2-CTD Rank: 2 Configured Clock Speed: 2666 MHz Minimum Voltage: 1.2 V Maximum Voltage: 1.2 V Configured Voltage: 1.2 V
