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Tests are too slow for libraries with eager-mode dispatch overhead

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#197 16 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
python

Research direction

Start with the linked GitHub Actions job and the array-api-tests suite to reproduce the reported 4.5-hour run and inspect which tests dominate runtime. The issue does not name source files or test entry points; done means substantially reducing eager-mode test time while preserving the suite's compliance coverage and results.

Written by the indexing model from the issue text.

Description

For example this job: https://github.com/google/jax/actions/runs/6804780902/job/18502996983, which is associated with https://github.com/google/jax/pull/16099 took 4.5 hours to run about 1000 tests.

========== 567 failed, 439 passed, 116 skipped in 16419.47s (4:33:39) ==========

This is slow enough to be virtually unusable.

Is there anything I can do to speed up the tests during development of the JAX array API?

Edit: as mentioned below, this is due to the frequent use of patterns within the tests that every value in each array via indexing, and the fact that in eager execution, each of these indexing operations have a small dispatch overhead that leads to slow tests when arrays are large.

Dominant language
Python
Stars
74
Forks
54
Avg merge
4h 35m
Merged PRs (30d)
4

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