GEOS-ESM / GEOS-ESM/GOCART

bugs on nSubsteps

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Dominant language
Fortran
Stars
29
Forks
22
Avg merge
1d 16h
Merged PRs (30d)
4

Description

It was reported and confirmed by me that nSubSteps becomes zero here ( both main and develop branch)
https://github.com/GEOS-ESM/GOCART/blob/c393e57d4472c06ec61b770f8f46a152fd3280ff/Process_Library/GOCART2G_Process.F90#L1579-L1580

It turns out dt_cfl is a big negative value when it crashes. We can add a protection to set nSubSteps to zero. But I am wondering if the bug is from the other place that makes dt_cfl negative

@amdasilva

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First steps

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Research direction

Start at Process_Library/GOCART2G_Process.F90 lines 1579-1580 and trace where dt_cfl is calculated and becomes negative. Reproduce the crash on the main or develop branch, then determine whether the failure is upstream or requires protection around nSubSteps. Done means the negative-dt_cfl path no longer crashes and its behavior is covered by an appropriate test or reproduction.

Written by the indexing model from the issue text.

Assessment

Tech stack
fortran
Domain
backend
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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