截止2023年11月re-Invent 2023，新的7系列EC2已经发布，第四代EPYC处理器已经发布，因此本文介绍的内容不再是最新版本。关于7系列，请参考这篇博客。
云上EC2使用AMD处理器的哪一种机型？调查结果请参考如下。
一、AWS云上机型
创建一个使用Linux操作系统的EC2，登陆后执行lscpu命令即可查看其CPU信息。
1、较老的t3a机型
查看结果如下：
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 48 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Vendor ID: AuthenticAMD
BIOS Vendor ID: Advanced Micro Devices, Inc.
Model name: AMD EPYC 7571
BIOS Model name: AMD EPYC 7571
CPU family: 23
Model: 1
Thread(s) per core: 2
Core(s) per socket: 1
Socket(s): 1
Stepping: 2
BogoMIPS: 4398.76
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mm
xext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid tsc_known_freq pni pclmul
qdq ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cmp_legacy cr8_legacy a
bm sse4a misalignsse 3dnowprefetch topoext vmmcall fsgsbase bmi1 avx2 smep bmi2 rdseed adx smap clflushopt sha_ni
xsaveopt xsavec xgetbv1 clzero xsaveerptr arat npt nrip_save
Virtualization features:
Hypervisor vendor: KVM
Virtualization type: full
Caches (sum of all):
L1d: 32 KiB (1 instance)
L1i: 64 KiB (1 instance)
L2: 512 KiB (1 instance)
L3: 8 MiB (1 instance)
NUMA:
NUMA node(s): 1
NUMA node0 CPU(s): 0,1
Vulnerabilities:
Itlb multihit: Not affected
L1tf: Not affected
Mds: Not affected
Meltdown: Not affected
Mmio stale data: Not affected
Retbleed: Mitigation; untrained return thunk; SMT vulnerable
Spec store bypass: Vulnerable
Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Spectre v2: Mitigation; Retpolines, STIBP disabled, RSB filling, PBRSB-eIBRS Not affected
Srbds: Not affected
Tsx async abort: Not affected2、较新的c6a机型
查看结果如下：
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 48 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Vendor ID: AuthenticAMD
BIOS Vendor ID: Advanced Micro Devices, Inc.
Model name: AMD EPYC 7R13 Processor
BIOS Model name: AMD EPYC 7R13 Processor
CPU family: 25
Model: 1
Thread(s) per core: 2
Core(s) per socket: 1
Socket(s): 1
Stepping: 1
BogoMIPS: 5299.99
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mm
xext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf tsc_known_freq
pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm
cmp_legacy cr8_legacy abm sse4a misalignsse 3dnowprefetch topoext invpcid_single ssbd ibrs ibpb stibp vmmcall fsgs
base bmi1 avx2 smep bmi2 invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 clzero xsaveerptr
rdpru wbnoinvd arat npt nrip_save vaes vpclmulqdq rdpid
Virtualization features:
Hypervisor vendor: KVM
Virtualization type: full
Caches (sum of all):
L1d: 32 KiB (1 instance)
L1i: 32 KiB (1 instance)
L2: 512 KiB (1 instance)
L3: 4 MiB (1 instance)
NUMA:
NUMA node(s): 1
NUMA node0 CPU(s): 0,1
Vulnerabilities:
Itlb multihit: Not affected
L1tf: Not affected
Mds: Not affected
Meltdown: Not affected
Mmio stale data: Not affected
Retbleed: Not affected
Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl
Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Spectre v2: Mitigation; Retpolines, IBPB conditional, IBRS_FW, STIBP conditional, RSB filling, PBRSB-eIBRS Not affected
Srbds: Not affected
Tsx async abort: Not affected3、较新的m6a机型
查看结果如下：
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 48 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 2
On-line CPU(s) list: 0,1
Vendor ID: AuthenticAMD
BIOS Vendor ID: Advanced Micro Devices, Inc.
Model name: AMD EPYC 7R13 Processor
BIOS Model name: AMD EPYC 7R13 Processor
CPU family: 25
Model: 1
Thread(s) per core: 2
Core(s) per socket: 1
Socket(s): 1
Stepping: 1
BogoMIPS: 5299.97
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mm
xext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf tsc_known_freq
pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm
cmp_legacy cr8_legacy abm sse4a misalignsse 3dnowprefetch topoext invpcid_single ssbd ibrs ibpb stibp vmmcall fsgs
base bmi1 avx2 smep bmi2 invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 clzero xsaveerptr
rdpru wbnoinvd arat npt nrip_save vaes vpclmulqdq rdpid
Virtualization features:
Hypervisor vendor: KVM
Virtualization type: full
Caches (sum of all):
L1d: 32 KiB (1 instance)
L1i: 32 KiB (1 instance)
L2: 512 KiB (1 instance)
L3: 4 MiB (1 instance)
NUMA:
NUMA node(s): 1
NUMA node0 CPU(s): 0,1
Vulnerabilities:
Itlb multihit: Not affected
L1tf: Not affected
Mds: Not affected
Meltdown: Not affected
Mmio stale data: Not affected
Retbleed: Not affected
Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl
Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Spectre v2: Mitigation; Retpolines, IBPB conditional, IBRS_FW, STIBP conditional, RSB filling, PBRSB-eIBRS Not affected
Srbds: Not affected
Tsx async abort: Not affected4、截止2023年7月尚在Preview的c7a机型
暂无信息。
以上信息来自使用者的配置，现在查看官方信息。
二、官方信息（来自AMD官网）
通用型 m6a/m5a 机型（vCPU和内存比1:4）的处理器信息：
计算优化型 c6a/c5a 机型（vCPU和内存比1:2）的处理器信息：
内存优化型 r6a/r5a （vCPU和内存比1:8）机型的处理器信息：
爆发型 t3a （vCPU和内存1:0.5/1:1/1:2/1:4）机型的处理器信息：
GPU-3D图形场景型 g4.ad（vCPU和内存比1:4）的处理器信息：
三、结论
用于生产系统的c6a、m6a、r6a系列的EC2都是第三代EPYC处理器（代号Milan）的处理器。用于开发测试系统的爆发型t3a系列的处理器是第一代EPYC处理器，性能不高，主打性价比。
使用第四代EYPC处理器（代号Genoa）的c7a等机型截止2023年7月尚未大规模可用，不久的将来也会商用推向市场。
四、参考文档
AWS官网对AMD处理器的介绍：
https://aws.amazon.com/cn/ec2/amd/
AMD官网介绍AWS云服务机型：
https://www.amd.com/en/processors/amd-epyc-aws
AWS官网型发布m7a型介绍：