---
id: "bug-1899"
status: "open"
status_updated: "2026-10-01"
status_note: "newly logged"
component: "apiserver"
severity: "wrong-result"
timestamp: "2026-10-01T05:10:35Z"
last_seen: "2026-10-01T05:10:35Z"
occurrences: 1
files: ["src/frontend/apiserver/controllers/jobs.go"]
tags: ["apiserver", "control", "job-array", "code-review"]
related: ["bug-1898", "bug-1896"]
---

# bug-1899: ControlJobByID re-dispatches earlier selections on every later selection of one request

## Description
**Observed:** found by code review, no failing run captured yet. In `ControlJobByID` the slice `successJobs` is declared once before the loop over the request's selections (`src/frontend/apiserver/controllers/jobs.go:2464`), is appended to inside that loop (`:2575-2583`), and the dispatch loop over the whole accumulated slice also sits inside it (`:2594-2617`):
```go
successJobs := []map[string]interface{}{}            // :2464, outside
for _, ujobFilterCdArray := range allFiltCdArrays {   // one per selection
    ...
    successJobs = append(successJobs, ...)           // :2575
    if len(successJobs) > 0 {
        for _, successJob := range successJobs {      // re-sends all earlier ones
            err = backend.ControlJob(...)              // :2611
```
**Expected:** each selected job receives the control action once per request; the response lists it once.
**Impact:** wrong result: `xcecli jobs kill X[1],Y[2]` (or `kill A,B`) signals the first selection's jobs once per later selection (N selections -> the first job is sent N times); a repeated kill of an already-killed job can make the backend call fail and the request report an error; `BuildBatchOperationResponse` receives the accumulated slice, so the response lists earlier jobs repeatedly. Distinct from the out-of-scope duplicate-signal case of one element selected twice (job-array-one-based-index requirements).
**Found by:** review (design review round 11 of spec `job-array-one-based-index`, 2026-10-01)

## Environment
- OS: no /etc/os-release; Docker container; NixOS kernel; kernel Linux 6.18.33 x86_64
- libc: n/a (pure-Go control handler); host glibc 2.40
- Toolchain: gcc (GCC) 15.2.0, meson 1.9.1
- Build: asan (xce.build); defect is in pure Go, independent of profile
- Code: scheduler-framework @ 8f5ba635-dirty
- Deployment: any (single-node or HA) with at least two controllable jobs

## Reproduction
1. Read `src/frontend/apiserver/controllers/jobs.go:2464-2620` (`ControlJobByID`): the `backend.ControlJob` loop over `successJobs` is inside the per-selection loop.
2. Live: submit two `sleep 300` jobs A and B; `xcecli jobs stop A,B`; the controller log shows the stop for A twice.
- Frequency: deterministic (by code reading; not yet run)
- Evidence: not kept (code reading only)

## Root cause
TODO: required for fixed/partial

## Fix
TODO: required for fixed/partial

## Verification
- Test: TODO: name + file; RED before the fix, GREEN after
- Suites: TODO: suite results and build profile
- Live: TODO: soak/deploy run, or n/a and why

## References
- Related: bug-1898 (same review), bug-1896 (spec job-array-one-based-index restructures this handler)