jgfs_vminmon ecf (v17) Analysis

jgfs_vminmon.ecf (GFS v17)

Branch / tenant: dev/gfs.v17 (gw_v17) Path: ecf/scripts/gfs/verf/atmos/jgfs_vminmon.ecf Analysis date: 2026-06-11 Method: On-disk analysis of v17 worktree.

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Summary

jgfs_vminmon.ecf is the NCO production ecFlow task that runs the GSI Variational Minimization Monitor (VMinMon) for the GFS cycle. It extracts and archives convergence diagnostics from the atmospheric analysis, tracking the minimization behavior of the GSI variational solver. It calls JGLOBAL_ATMOS_VMINMON.

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1. The script itself

Section	Detail
PBS resources	1 node, 1 cpu, 1 GB, 5-min wall, shared
Modules	load_modules.sh gsi (GSI monitoring tools)
J-Job	JGLOBAL_ATMOS_VMINMON
Rocoto breadcrumb	vminmon.sh

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2. Execution chain

jgfs_vminmon.ecf
  +-- JGLOBAL_ATMOS_VMINMON
       +-- exglobal_atmos_vminmon.sh (or Python equivalent)
            +-- Extracts GSI minimization statistics
            +-- Archives convergence data for monitoring

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3. What the J-Job produces

Product	Description
Minimization convergence stats	Cost function / gradient norm per iteration
Time-series data	Appended to operational monitoring archive

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4. v17-specific notes

• Tiny resources: 1 cpu, 1 GB, 5 min — simply parses GSI output logs.
• GSI modules: loads gsi module set (not ufsda or ufswm).
• Monitoring only: does not affect operational products; failure is non-critical.
• Depends on: atmospheric analysis completion (reads its output).

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5. Change-impact snapshot

Symbol	Risk	Notes
JGLOBAL_ATMOS_VMINMON	LOW	Monitoring suite leaf

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Sources

• On-disk v17 worktree: ecf/scripts/gfs/verf/atmos/jgfs_vminmon.ecf.