Snapshot contention leaves lock artifacts and disk churn

[riatzukiza]

Problem

Under heavy session activity, snapshot operations can overlap on the same snapshot git dir. This can leave index.lock / temporary pack artifacts and cause avoidable disk churn.

Scope

• Serialize snapshot operations per snapshot repo
• Harden staging/tree-write behavior under lock contention
• Make cleanup lock-aware and threshold-driven
• Add regression tests for high-contention behavior

Notes

This issue tracks phased fixes to reduce lock races and stabilize long-running sessions using snapshot-heavy workflows.

[github-actions]

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What needs to be fixed:

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This issue might be a duplicate of existing issues. Please check:

• Snapshot system leaks tmp_pack_* files indefinitely, filling disk at ~9.5 GB/hour #14811: Snapshot system leaks tmp_pack_* files indefinitely — same disk churn from snapshot operations
• [ROOT CAUSE ANALYSIS] tmp_pack Leak - Complete Code Analysis & Fix Recommendations #10034: Root cause analysis of tmp_pack leak — covers lock contention, staging failures, and cleanup gaps
• Snapshot.track() silently swallows git add failures, causing data loss on /undo #12719: Snapshot.track() silently swallows git add failures — directly related to staging/tree-write behavior under failure conditions

If you believe this was flagged incorrectly, please let a maintainer know.

[github-actions]

This issue has been automatically closed because it was not updated to meet our contributing guidelines within the 2-hour window.

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