Can't run ACAS Xu example

[ckessler2]

When running these commands:

vehicle verify
--specification acasXu.vcl
--verifier Marabou
--network acasXu:acasXu_1_7.onnx
--property property3

I get this error:

Verifying properties:
property3 [......................................................] 0/1 queries
Error: Marabou was automatically killed by the OS with signal '4'.
The most common reason for this is an out-of-memory-error.

When running compile and verify separately, compile works but verify gives same error. The files passed are attached, although they should be identical to the originals.
acasXu.zip

Module versions: maraboupy==1.0.0, vehicle-lang==0.11.0

OS is Ubuntu 22.04.3 LTS (jammy) running in WSL 2 on Windows 10 Pro, and I have 16gb of RAM available. I have set WSL to use all 16gb in its config (grep MemTotal /proc/meminfo returns 16gb) and tried WSL 1.

According to time the command runs for 0.186s and there is no visible increase in memory on task manager - compared to 44s and a significant increase when running the mnist-robustness example (which runs fine).

[MatthewDaggitt]

Hmm so it looks like this is a problem on the Marabou end. But Vehicle's diagnosis is wrong, Marabou isn't running out of memory. Error code 4 is "illegal instruction". So there's something buggy in your build of Marabou.

Can you run

vehicle compile 
  --target MarabouQueries
  --specification acasXu.vcl
  --network acasXu:acasXu_1_7.onnx
  --property property3
  --output queries

and then run

Marabou
  acasXu_1_7.onnx
  queries/property3-query1.txt

and report the output? (I haven't tested that command myself. The first one compiles the queries, and the second one runs Marabou explicitly to capture it's full output).

[MatthewDaggitt]

I've also transferred this issue to the main Vehicle repo.

[ckessler2]

It outputs this:

Network: acasXu_1_7.onnx
Property: queries/property3-query1.txt

Engine::processInputQuery: Input query (before preprocessing): 314 equations, 615 variables
Engine::processInputQuery: Input query (after preprocessing): 614 equations, 861 variables

Input bounds:
        x0: [ -0.3035,  -0.2986]
        x1: [  0.0000,   0.0095]
        x2: [  0.4934,   1.0000]
        x3: [  0.3000,   0.4091]
        x4: [  0.3000,   0.5000]

Illegal instruction (core dumped)

I will try reinstalling marabou in case it changes anything

[wenkokke]

Try compiling Marabou from source. This error implies that the binaries that you are using were compiled for a newer CPU.

Would you be able to post the contents of /proc/cpuinfo?

[ckessler2]

I did compile Marabou from source, as per these instructions https://neuralnetworkverification.github.io/Marabou/Setup/0_Installation.html

/proc/cpuinfo returns this 12 times:

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 151
model name      : 12th Gen Intel(R) Core(TM) i5-12400F
stepping        : 2
microcode       : 0xffffffff
cpu MHz         : 2496.000
cache size      : 18432 KB
physical id     : 0
siblings        : 12
core id         : 0
cpu cores       : 6
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 21
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 syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid pni pclmulqdq ssse3 fma cx16 pdcm pcid sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single ssbd ibrs ibpb stibp ibrs_enhanced fsgsbase bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves umip gfni vaes vpclmulqdq rdpid fsrm flush_l1d arch_capabilities
bugs            : spectre_v1 spectre_v2 spec_store_bypass swapgs retbleed eibrs_pbrsb
bogomips        : 4992.00
clflush size    : 64
cache_alignment : 64
address sizes   : 39 bits physical, 48 bits virtual
power management:

[wenkokke]

It appears that the binaries distributed via PyPI require AVX-512, which your CPU does not support. (The full list of CPU extensions that are required but unsupported is AVX512, MODE64, BWI, NOVLX, VLX, and DQI, but I'm no expert, so some of these could be due to aliasing.)

As you're compiling from source, I'm unsure if the same is true for the binaries you've built. You can verify the CPU extensions required by the binary you've built by running elfx86exts.

Either way, this appears to be an issue with the way in which Marabou is built. I can submit an upstream issue, if you can provide me with some information:

1. Run the following command from examples/acasXu:

   vehicle compile -s acasXu.vcl -t MarabouQueries -n acasXu:acasXu_1_7.onnx -e property3 -o property3

   Please attach the file property3/property3-query1.txt to your response.

2. Run the following command from examples/acasXu to verify that it results in a similar error message:

   Marabou --input-query property3/property3-query1.txt

   Please include the output and error message in your response.

3. Run the following command:

   file $(which Marabou)

   If the command outputs "ASCII text", "Bourne-Again shell script", "Python script", or anything that gives you the impression it's a text file, find the path to your Marabou executable with the following command:

   python -c "import maraboupy.MarabouCore; print(maraboupy.MarabouCore.__file__)"

   Otherwise, find the path to your Marabou executable with the following command:

   which Marabou

   Then, either:

   • Attach the Marabou executable to your response.
   • Determine the CPU extensions required by the Marabou executable, and include those in your response.

   To determine the CPU extensions required by the Marabou executable:

   • Install elfx86exts.

     # install rust
     curl https://sh.rustup.rs -sSf | sh
     # install elfx86exts
     cargo install elfx86exts

   • Run the following command, replacing $PATH_TO_MARABOU with the path you found:

     elfx86exts $PATH_TO_MARABOU

     Please include the output in your response.

[wenkokke]

Follow up:

• DQI is AVX-512 Doubleword and Quadword Instructions
• BWI is AVX-512 Byte and Word Instructions
• VLX is AVX-512 Vector Length eXtensions

So we can pretty confidently say the problem is due to the lack of AVC-512 support.

[ckessler2]

1: property3-query1.txt

2: It doesn't result in the same error I think, but here is the full output: Step_2_Output.txt

3:

File format and CPU architecture: Elf, X86_64
MODE64 (call)
SSE2 (movdqa)
SSE1 (movaps)
CMOV (cmove)
AVX (vmovsd)
NOVLX (vxorps)
AVX512 (vpmaxsq)
VLX (vpmaxsq)
BMI2 (shlx)
AVX2 (vpxor)
DQI (kmovb)
BWI (kmovd)
Instruction set extensions used: AVX, AVX2, AVX512, BMI2, BWI, CMOV, DQI, MODE64, NOVLX, SSE1, SSE2, VLX
CPU Generation: Unknown

[wenkokke]

That's a succesful run... That's... confusing.

AND the executable you're running uses AVX-512 instructions... which your processor doesn't seem to support?

[ckessler2]

I got the same 'out-of-memory' error when running the example on the Linux machine in the office, which has all the libraries installed and up to date.

However, Ben can run the example on his laptop, which has a different version of Marabou - "origin/negative-dimensions-fix 8d26b936" retrieved on June 19th 2023. We haven't been able to find that version on the Marabou repository

[wenkokke]

I got the same 'out-of-memory' error when running the example on the Linux machine in the office, which has all the libraries installed and up to date.

However, Ben can run the example on his laptop, which has a different version of Marabou - "origin/negative-dimensions-fix 8d26b936" retrieved on June 19th 2023. We haven't been able to find that version on the Marabou repository

Do you think that's a genuine out of memory error this time?

[ckessler2]

No, because it has 29gb available and exits after <1s as before

[wenkokke]

And in both cases you've built Marabou from source?

[ckessler2]

After reinstalling everything I have solved the problem - although the output:

Verifying properties:
  property3 [======================================================] 1/1 queries
    result: ✗ - counterexample found
      x: [1799.988667, 1.950928632e-2, 3.09999732192, 980.0, 1017.6036]

is different to the tutorial example:

Verifying properties:
  property3 [======================================================] 1/1 queries
    result: ✗ - counterexample found
      x: [1799.9886669999978, 5.6950779776e-2, 3.09999732192, 980.0, 960.0]

I'm working on recreating the issue so I can find the exact cause

[MatthewDaggitt]

I wouldn't worry about too much. I really doubt that Marabou (and all the downstream tools it uses) make much effort in to ensuring stability of counter-examples across different platforms. As long as the overall answer is the same, i.e. counterexample or proved, then I think it's fine 👍