> ## Antithesis CPUID info

> Fetch the complete documentation index at: https://antithesis.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

---

These are the reported properties of the simulated CPU in the Antithesis environment. If your software assumes or requires a specific modern CPU feature, check the `flags` list by running the `cpuid` command in the Antithesis environment to see if we support it out of the box.

For convenience, here are the feature flags it will report:

```python
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 85
model name      : Antithesis VM v1
stepping        : 7
cpu MHz         : [VARIES BASED ON ANTITHESIS CONFIGURATION]
cache size      : 33792 KB
physical id     : 0
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 22
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
                pat pse36 clflush mmx fxsr sse sse2 ss ht pbe syscall nx
                pdpe1gb lm constant_tsc rep_good nopl xtopology nonstop_tsc
                cpuid tsc_known_freq pni pclmulqdq dtes64 ds_cpl ssse3 sdbg
                fma cx16 xtpr pcid dca sse4_1 sse4_2 movbe popcnt aes xsave
                avx f16c hypervisor lahf_lm abm 3dnowprefetch cat_l3 cdp_l3
                invpcid_single mba fsgsbase bmi1 avx2 bmi2 erms invpcid
                avx512f avx512cd xsaveopt arat
bugs            : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds
                swapgs itlb_multihit mmio_stale_data retbleed
bogomips        : [VARIES BASED ON ANTITHESIS CONFIGURATION]
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:
```

As noted in our [security whitepaper](https://antithesis.com/security/manifesto/) every Antithesis customer runs on separate and dedicated physical infrastructure, so there is no risk of data exfiltration due to CPU vulnerabilities caused by shared microarchitectural state.