erroropensession-storejavascript

Error: session <uuid> evicted before write completed

src/session/flush.js#flushSession

Events251
First seen12d ago2026-08-11 16:24:38 UTC
Last seen11d ago2026-08-12 15:38:23 UTC
Releases1.9.0

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How this group was decided

Every step below is a pure function of the event. The same event always produces the same group.

  1. 1 · Parse the stack trace

    3 frames parsed, 2 belong to the application. Only those decide the group — the same bug reaches the runtime through different framework paths depending on the request.

    • in-appsrc/session/flush.js.flushSessionsrc/session/flush.js:94
    • in-appTimeout._onTimeoutsrc/session/reaper.js:28
    • vendornode:internal/timers.listOnTimeoutnode:internal/timers:594

  2. 2 · Build the fingerprint input

    Line numbers are dropped so that editing a line above the throw site does not open a new group. Values inside the message are replaced with placeholders.

    v1
platform=javascript
service=session-store
type=Error
frame=src/session/flush.js#flushSession
frame=Timeout#_onTimeout

  3. 3 · Hash it

    SHA-256 of the text above, truncated to 128 bits. The version is part of the group key: a future algorithm opens new groups rather than rewriting these.

    Fingerprint
    94c73c3ba69018baecb3071a9955c12c
    Algorithm version
    v1

Latest stored event

2026-08-12 15:38:23 UTC

session 5074dd0f-7242-4820-b12c-8b80579d3867 evicted before write completed

Error: session evicted before write completed
    at flushSession (/app/src/session/flush.js:94:13)
    at Timeout._onTimeout (/app/src/session/reaper.js:28:7)
    at listOnTimeout (node:internal/timers:594:17)

Similar groups

Trigram similarity computed by Postgres against a GIN index. It catches what a fingerprint cannot — the same fault one refactor away from an existing group. No model is involved.

Nothing above the 0.3 similarity threshold.