Scalability break-down in `NNLSSolver` for more than 2 processors

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#272 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
28/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp

Research direction

Start with the scalability test in tests/test_NNLS on the par-nnls branch and inspect the NNLSSolver path used for processor counts above two. Reproduce the reported timings on a comparable setup, then investigate the connection to issue #269. Done means the test no longer shows the reported slowdown as processor count increases.

Written by the indexing model from the issue text.

Description

bug

Scalability test using the unit test tests/test_NNLS in par-nnls branch shows a significant slow-down when more than 2 processors are used:

Number of processors Time
1 382ms
2 249ms
3 10902ms
4 15296ms

This test result is from a m2-chip macbook.

This issue might be related to #269 .

Dominant language
C++
Stars
236
Forks
47
PR merge metrics
No merged PRs in 30d

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