Add SHM_LOCK_DIR environment variable for containerized deployments (memory leak fix)#7312
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TheMarex merged 3 commits intoProject-OSRM:masterfrom Jan 8, 2026
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Allows specifying a custom directory for shared memory lock files via the OSRM_LOCK_DIR environment variable. This enables containerized deployments to persist lock files across container restarts, preventing crashes when using shared memory (osrm-routed -s)
TheMarex
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Jan 7, 2026
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This change makes sense. Please add an entry to the changelog. Let me know if you have time to do the small edits yourself, otherwise I can try to put this on my TODO for the week.
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Thanks for the review @TheMarex. changes pushed. |
TheMarex
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Jan 7, 2026
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Problem
OSRM crashes with
"lock file does not exist"when using shared memory (osrm-routed -s) in containerized environments (Kubernetes) after a container restart.The crash triggers a restart/crash loop, and each restart accumulates orphaned shm segments, leaking memory proportional to the graph size until the node is exhausted.
Related issues: #5134, #5703
Reproduction
See gist: https://gist.github.com/wes4m/719cb69b72e26c09c7ff57ed71cf33d9
Why This Happens in Containers
OSRM's shared memory implementation assumes
/tmpand System V shared memory have the same lifecycle. This is true on traditional systems where both are cleared on reboot, but not in containers:/tmpfilesystemWhen a container restarts:
/tmpis reset and lock files get deletedSharedRegionRegister(in shm) still references old segmentsSolution
This PR adds
OSRM_LOCK_DIRenvironment variable to specify a custom directory for lock files. This allows containerized deployments to place lock files in a volume that persists across container restarts (e.g. kubernetesemptyDir)Other Approaches
Mounting
/tmpto a persistent volume fixes the issue but will persist all temporary files from the container, not just lock files. SettingTMPDIRwill do the same, and cleaning orphaned shm segments on startup is a workaround that doesn't address the root cause.OSRM_LOCK_DIRonly affects lock file location and is backward compatible (tmp dir fallback), behavior is unchanged.