moss-decoder 0.4.0

Python package implemented in Rust to decode MOSS readout data

MOSS Decoder

Python module implemented in Rust for decoding raw data from the MOSS chip (Stitched Monolithic Pixel Sensor prototype).

• MOSS Decoder
  • Installation
  • Motivation & Purpose
  • @CERN Gitlab installation for CentOS and similar distributions from local build
    • Troubleshooting

Installation

$ pip install moss-decoder

Import in python and use for decoding raw data.

import moss_decoder
moss_packets = moss_decoder.decode_event(bytes)

Motivation & Purpose

Decoding in native Python is slow and the MOSS verification team at CERN got to a point where we needed more performance.

Earliest version of a Rust package gave massive improvements as shown in the benchmark below.

Decoding the 10 MB MOSS readout data. Performed on CentOS Stream 9 with Python 3.11

Command	Mean [s]	Min [s]	Max [s]	Relative
python moss_test/util/decoder_native_python.py	36.319 ± 0.175	36.057	36.568	228.19 ± 2.70
python moss_test/util/decoder_rust_package.py	0.159 ± 0.002	0.157	0.165	1.00

@CERN Gitlab installation for CentOS and similar distributions from local build

If you update the package source code and want to build and install without publishing and fetching from PyPI, you can follow these steps.

The .CERN-gitlab-ci.yml file contains a build-centos manual job which will build the MOSS decoder package from source and saves the package as an artifact.

1. Start the job, download the artifacts.
2. Unzip the artifacts and you will find a wheels package in /target/wheels/ with the .whl extension
3. Run python -m pip install <wheels package>.whl
4. Confirm the installation with python -m pip freeze | grep moss, it should display something containing moss_decoder @ file:<your-path-to-wheels-package>

Troubleshooting

if you get ERROR: Could not find a version that satisfies the requirement ... make sure to add .whl when performing step 3 above.

if you don't see the expected message at step 4, try running the installation command in step 3 with any or all of these options --upgrade --no-cache-dir --force-reinstall.