---
id: "bug-1420"
status: "fixed"
status_updated: "2026-09-24"
status_note: ""
component: "controller"
severity: "unknown"
timestamp: "2026-07-08T04:00:00.000Z"
last_seen: "2026-09-19T09:00:00Z"
occurrences: 1
files: ["src/controller/testsuite/test.c"]
tags: ["test-harness", "jobid", "idgen", "chaotic-soak", "false-positive"]
related: ["bug-1419"]
legacy: true
---

# bug-1420: xce_test CLI harness generates colliding jobids across separate process invocations within the…

## Description
xce_test CLI harness generates colliding jobids across separate process invocations within the same wall-clock second, surfacing as a spurious APPLY_DIVERGENT fence in chaotic HA soak (misattributed at first to bug-1419's controller-side dedup logic).

## Environment
_Not recorded (migrated from buglog.json)._

## Reproduction
_Not recorded (migrated from buglog.json)._

## Root cause
idgen() (src/lib/idgen.c) derives jobid from a per-context {timestamp (1s resolution), sequence (reset to 0 whenever the second rolls over or the context is freshly initialized)} pair, plus caller-supplied clusterId/apiserverId bits (src/include/config.h: 6+4 bits respectively) that are meant to partition the jobid namespace across independent generators. xce_test's cmd_jsub called idgen(&idctx, 0, 0, arsize, ...) -- both partition fields hardcoded to 0 -- so every xce_test process shares the SAME (degenerate, unpartitioned) jobid space. run-ha-soak.sh's submit_jobs() (run-ha-soak.sh:446) spawns a fresh xce_test process per submit/retry attempt (`printf script | xtest`, xtest() = `timeout 60 "$XT"`), and idgen_ctx_init() resets sequence=0 on every fresh process start. Two unrelated job submissions from two different xce_test process launches landing in the same wall-clock second therefore compute an IDENTICAL jobid (ts, tag, seq all equal) -- a genuine, reproducible collision between logically distinct jobs, not a retry of the same one. This is NOT a production defect: apiserver's GenerateJobID (src/frontend/apiserver/backend/clib.go) initializes its idgen_ctx_t exactly once per process via sync.Once (sequence only resets on an actual apiserver restart, far rarer than per-request), and each deployed apiserver instance is assigned its own distinct apiserverId, so config.h's bit layout already partitions the production jobid namespace across instances even in the rare restart-collision case.

## Fix
Folded getpid() into the harness's apiserverId at the idgen() call site (test.c:1868): idgen(&idctx, 0, (size_t)((uint64_t)getpid() & MAX_APISERVER_ID), arsize, &(jobsubmit.jobid)) -- gives every xce_test process invocation its own slice of the same namespace partitioning production already relies on, making a same-second cross-process collision structurally impossible. Mechanical, test-tool-only change; no production code touched. Verified via clean rebuild of both xce_test and controller_unit_test targets (no coupling, no regressions).

## Verification
_Not recorded (migrated from buglog.json)._

## References
- Related: bug-1419