Adds a NULL-by-default lookup/populate callback seam on xce_sched_core_t,
mirroring cache_clear_cb's proven shape, so the allocation dispatch
chokepoint can consult the unsatisfiable-resreq cache without a
normal-mode-only field access in shared code. Adapters live in
alloc_cache.c and are registered only during normal-mode startup;
simulation mode leaves both callbacks NULL and always computes fresh.
Adds the scheduler-sim-live-allocation spec (requirements/design/
research/tasks) as the planning artifact this and subsequent tasks
implement against.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RLSNJhNoULvVcUhXEFafQC
Clear the cache inside core_begin_session_internal() so a job cached as
unsatisfiable in one session is re-evaluated fresh in the next (Req 7.2).
An initial weak-symbol cast-based approach was rejected: it corrupted
xce_sched_sim_driver_t.alt_events_file, since core_begin_session_internal()
is shared between driver.c (real xce_scheduler_t) and sim_loop.c (a
structurally different, deliberately isolated sim driver struct with no
cache field at the same byte offset) -- the strong cache_clear() symbol
won unconditionally for both, invisible to ASAN and untested by any
test_sim_*.c file.
Fixed via a driver-registered callback: xce_sched_core_t gains a
cache_clear_cb hook (NULL by default, per xce_sched_core_init()'s
full-struct memset), set only in main.c's driver-mode branch --
mirroring the existing on_decision/xce_core_set_decision_cb() pattern.
--sim mode returns before that registration is ever reached, so its hook
stays NULL and core_begin_session_internal()'s guarded call is a no-op.
The real xce_scheduler_t-casting adapter lives in alloc_cache.c rather
than driver.c, since ~11 tests white-box-include driver.c without
linking alloc_cache.c.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XYdtrEWWZfKRRGED7raEYg
Adds reservation-vs-actual-usage reconciliation for real (gauge-style)
resources, using mem as the concrete case -- documented in the new
resource-accounting.md steering doc.
Policy: charged = max(reserved, actual). A job's rusage[mem=...]
request is an estimate made before it has run, and the real usage the
worker later reports may land above or below it; charging a flat
reservation for the job's whole life either starves other jobs of
memory it never uses (when actual stays below the estimate) or lets
the host be driven into genuine oversubscription (when actual exceeds
it). Available memory for scheduling is then the host's OS-reported
available figure minus, per job, only the UNUSED SLACK of the
reservation (max(0, reserved - used)) -- never the job's actual usage
on top of that, since the OS's own figure already reflects it.
The existing xce_res_account_t{used, reserved, allocated} fields and
sched_update_res_accounts()'s used+reserved charge formula already
implement this exactly, once `used` is set to the OVERAGE beyond the
reservation (max(0, actual - reserved)) rather than left at its
permanent 0.0 default -- nothing previously computed it.
New (resource.c): sched_reconcile_host_resource_usage() sets that
overage on one xce_res_account_t and applies just the DELTA to the
affected worker's resInUse (not a full uncharge/recharge of the whole
job_account, which would needlessly re-touch sibling resources like
"slots" charged in the same account). sched_reconcile_job_resource_usage()
is the wrapper driven from a raw rusage report: maps the worker's real
wire resname ("memory_rss", same worker-resname-vs-scheduler-resource-
name split bug-1735 already established for the controller side) to
the scheduler's "mem" resource, and is a no-op when the job spans more
than one host (the wire report carries no per-host attribution today --
a separate, undocumented-until-now gap, out of this fix's scope) or
never requested rusage[mem=...] in the first place (reserved=0, nothing
to reconcile).
Wired into sched_apply_job_rusage() (schedobj.c), which already
receives every job rusage tick but previously only stored it for
display/plugin hooks with no resource-accounting effect at all.
Compatible with sched_account_jobs()'s existing per-round resInUse
reset+re-derive cycle (bug-1624): the reconciled `used` value is
persisted on the job's own account record, which that re-derivation
already reads from, not just a transient pool-level delta that a
round boundary would wipe.
Added link-satisfying stubs to the three white-box test files that
#include schedobj.c directly (test_job_update.c,
test_picker_config_fields.c, test_picker_wiring.c) -- none of them
exercise real job->accounts, so the new call is unreachable there, but
still needs to link. 10 new regression tests in
test_resource_accounting.c cover the core formula (below/at/above the
reservation, delta-only pool updates, sibling-resource isolation) and
the wrapper's scoping rules (resname mapping, multi-host skip,
no-request no-op).
Full scheduler suite: 55/55 passing, zero regressions.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019QxaSzHRB7pmYFp4cVnwkA
sim_loop.c never called plugin_begin_session()/plugin_end_session() at
its round boundary, unlike driver.c's normal-mode round -- a driver-
equivalence gap found by an /xce-audit-invariants scheduler pass.
Currently inert (sim mode's only reachable picker, builtin_fcfs, leaves
both hooks NULL) but structurally identical to bug-1613's class of bug.
Relocated plugin_begin_session()/plugin_end_session() from an implicit
xce_scheduler_t* to xce_sched_core_t* directly (mirroring
sched_account_jobs()'s prior relocation) -- their bodies never touched
anything beyond core->plugins, so driver.c's comment claiming they
"needed the full xce_scheduler_t*" was itself stale. sim_loop.c now
calls both, same relative position as driver.c. A full-tree grep (done
after the first build attempt failed on an untouched file) turned up a
third live call site in scheduler.c's legacy sched_begin_session()/
sched_end_session(), plus four testsuite files with their own stub
definitions of the same functions -- all updated to match the new
signature.
Extended test_sim_session_ordering.c's existing bug-1613 regression
tests with new plugin_begin_session()/plugin_end_session() spies
(call-count + session_active-window proof, same technique as the
existing sched_account_jobs spy). RED/GREEN independently verified:
temporarily disabled the two new call sites, confirmed both new
assertions fail (Expected 2 Was 0 / Expected 1 Was 0), restored,
reconfirmed green. Full scheduler suite: 51/52 green, the one failure
is the pre-existing unrelated bug-1560 sandbox flake.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AgYRU3zDTqNGV5Jk8aiKLg
Relocates sched_account_jobs()/sched_charge_account()/sched_uncharge_account()/
sched_update_account()/sched_update_res_accounts()/sched_commit_job_alloc()
from xce_scheduler_t* to xce_sched_core_t*, mirroring the sched_resolve_job_picker()
precedent, so the simulation driver can call the same accounting service the
normal-mode driver already uses. Pure signature relocation -- every body
reference was already sched->core.*, no logic change. Updates the 3 real call
sites (driver.c's normal-mode round, scheduler.c's sched_begin_session and
sched_commit_decision) and 7 existing tests' link-satisfying stub signatures.
Adds test_resource_accounting.c proving Requirement 1.4: the relocated
accounting produces identical resInUse/sharedInUse output whether called
against a core embedded in xce_scheduler_t or xce_sched_sim_driver_t.
43/44 scheduler tests pass; the 1 failure is pre-existing bug-1560
(unrelated recording.c sandbox-permission ordering issue).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Bugs fixed, discovered across a day of live-operator testing against a
real deployed cluster:
- bug-1584: clock anchors never initialized to real wall-clock values,
timestamps showed system uptime instead of Unix epoch.
- bug-1585: heap-use-after-free in the normal-mode driver's periodic
resval update path -- core_events.c's RESVALS_FULL/_DELTA handlers do a
shallow zarray_put() of the wire-decoded xce_val_t*, but driver.c's
release_translated_payload() unconditionally freed the same decoded
array right after, so the next periodic report for the same
worker+resource triggered a UAF read via kill_sched_resval(). New
regression test: test_resval_ownership.c.
- bug-1587/1588/1591: raw-ns/raw-uint64 jobid/timestamp prints across the
REPL/SIM family converted to the same human-readable formatting already
used elsewhere (fmt_jobid(), timestamp formatting).
- bug-1590: repl_info.c's XCE_VAL_NUMERIC checks corrected to
Value_u_fvalue, fixing `info worker`/`info resource` falling back to
0.00 for real numeric resvals.
task 12.5 (Req 5.22 amendment) -- five REPL gaps surfaced by a live
operator session, each with its own bug id:
- bug-1594: `continue`/`step` reaching EOF with no breakpoint hit now
re-enters the REPL via xce_repl_on_replay_complete() instead of exiting
the process; step/continue issued after replay is already complete
re-prompt instead of silently exiting.
- bug-1595: `step`/`continue` now echo each input event (not just
decisions) via repl_print_event_summary(), in real event/decision
order.
- bug-1593: `info resource <name>|all` now reports resource definition
metadata restricted to XCE_RESF_GLOBAL/XCE_RESF_SHARED resources, read
from core->sharedInst, instead of aggregating host-based resources
across every worker.
- bug-1596: repl_split_tokens() strips one matching pair of surrounding
quote characters from each token.
See requirements.md's Req 5 AC 22 "Amendment (2026-08-19)" for the full
rationale on each of the five task 12.5 gaps.
Full scheduler suite green (41/42; the one remaining failure,
test_recordstart_symlink_escape_replies_error, is the pre-existing
unrelated bug-1560).
Adds xce_sched_core_save_snapshot()/xce_sched_core_load_snapshot(),
split across snapshot.c/snapshot_wire.c/snapshot_load.c (800-line cap)
along real save/load/shared-helper boundaries. Serializes the full
core state (config, jobs, queues, workers, resources, resvals, users,
projects, prng_seed, internal_state) into/out of sched_snapshot_data_t
(task 7.3's committed C mirror of the capnp SnapshotData struct) as
plain in-memory structures -- no wire encoding here, that's a later
task. After load, rebuilds the picker's private state by re-invoking
its state-change hooks (queue updates, then job pushes) against the
restored core state, matching xce_core_push_events()'s own hook-firing
order; picker-private state itself is never stored in the snapshot.
Adds a new prng_seed field to xce_sched_core_t -- requirements.md/
design.md both presuppose it but no prior task added it. Seeded to 0,
no PRNG consumer wired yet (deliberately out of scope).
Cross-core behavioral-equivalence proven directly: two independent
cores, each with its own registered picker, save on one and load into
a freshly-initialized other, both driven through an identical real
session, decision sequences asserted identical in order.
Found and fixed two real bugs along the way: a missing prng_seed
restore in this task's own new code, and a genuine guard bug in
already-committed core.c (sched_get_user()/sched_get_project()
treating key_find()'s expected -ENOENT as fatal, silently breaking
get-or-create for any new name) that also affects the live production
path (make_sched_job(), JOBS_PUSH) -- a narrowly-scoped two-line fix,
independently traced to the primitive level and confirmed correct by
review.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Rewires main.c's live scheduling loop onto the new core-driven
architecture: xce_sched_driver_translate_pending_events() (task 5.1)
-> xce_core_begin_session() -> plugin_begin_session()+sched_account_jobs()
-> xce_core_signal_go() -> decision-drain via the registered
xce_core_decision_cb_t -> plugin_end_session() -> xce_core_end_session(),
all in the new exported xce_sched_driver_run_normal_mode_round()
(driver.c), replacing the old inline sched_update()+sched_begin_session()
+sched_go()+switch+sched_end_session() sequence.
xce_core_go() (task 4.4) is split into xce_core_begin_session()/
xce_core_signal_go() -- a pure decomposition (xce_core_go() itself is
now defined in terms of both, task 4.4's approved test suite passes
unmodified) -- specifically so the driver can interleave
plugin_begin_session()/sched_account_jobs() in the exact safety-critical
window task 4.4 deliberately excluded from pure-core scope: after the
resval reset, strictly before the picker thread is signaled. This is
empirically proven by test_driver_session_ordering.c via real
cross-thread happens-before assertions, not just documented.
xce_sched_driver_on_decision() is the new registered callback:
DISPATCH/PEND forward to the existing sched_publish_dispatch()/
sched_publish_pend_reason(); PREEMPT fails loudly (-ENOSYS, logged)
since no xcecli_preempt() client API exists and nothing in the live
allocator produces one yet (scheduler-preemption's territory).
Adds a --sim CLI flag (parse-only, loud not-yet-implemented failure,
since SimDriver is Phase 3).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Adds xce_core_now() (new core_clock.c, kept separate from core.c so
test_core_isolation.c's wall-clock scan still enforces zero direct
clock_gettime()/time() calls elsewhere in the core): the two-anchor
plus speed formula (virtual_clock_base + (elapsed * speed_num) /
speed_den), covering all four modes (normal, discrete/real-time/fast-
slow simulation) via four new atomic fields on xce_sched_core_t,
defaulted to normal-mode (1/1 speed) in xce_sched_core_init().
requirements.md's literal tlog_reg_format_func(fn, core_ptr) call
shape doesn't exist in the real vendored tlog library (registration
takes only the callback; userptr is per-call-site, not bindable at
registration) -- resolved with a module-level active-core pointer read
by a new core-scoped format function, not wired into mylog_init()/
main.c yet. xce_core_go()/xce_core_end_session() (task 4.4) now stamp
session_start/compute session_duration_ns via xce_core_now(), with
their existing session-active/reentrancy behavior untouched.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Adds xce_core_go()/xce_core_end_session() (new core_session.c):
xce_core_go() is non-blocking, performs begin-session state reset
(select-eval-ctx, resval resets), signals the picker thread via wbuf,
and returns -EINVAL on a reentrant call while a session is already
active (proven a true no-op, not just an early return). Draining
core->decisions and invoking the driver's on_decision callback is the
driver's own responsibility between core_go() and core_end_session()
(confirmed driver-owned, not core-owned, per the Driver <-> Core
protocol). xce_core_set_decision_cb() registers the callback + driver
context as a separate setter, keeping xce_sched_core_init()'s live
sched_init() call site untouched. Adds XCE_DECISION_PREEMPT to
decision.h (jobid/victims[]/reason) alongside the existing DISPATCH/
PEND types. Additive only — sched_go/sched_begin_session/
sched_end_session/sched_allocator/main.c remain untouched.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Defines xce_core_event_type_t/xce_core_event_t (9 event kinds: config,
job, worker, resource, resval full/delta, job state change, job update,
queue update, job rusage) in core.h. Implements xce_core_push_events()
in a new core_events.c (split out of core.c to stay under the 800-line
cap): rejects -EBUSY mid-session, otherwise applies each event's core-
state mutation and fires the corresponding picker hook synchronously,
exactly once per event, before returning. CONFIG_PUSH decomposes the
pushed config's embedded queues/resources/resvals via shared helpers
(also reused by QUEUE_UPDATE's upsert path), mirroring the existing
sched_init_config()/sched_init_resources()/sched_init_sharedInst()/
sched_init_queues(). Narrows sched_resolve_job_picker() to take
xce_sched_core_t* (pure type change, zero behavior change). Purely
additive — not wired into the live scheduling path yet (task 5.x).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Splits xce_scheduler_t along the controller-I/O seam: xce_sched_core_t
(new core.h/core.c) now holds all scheduling state (jobs/queues/workers/
users/projects/resource managers/plugins/three-thread-cbuf pipeline),
while xce_scheduler_t shrinks to {core; apictx; cluster_cfg}. Proven via
an nm-based link-time isolation test (zero netio/xcecli/idgen/delaymgr
symbols reachable from core.c) plus a reproducible wall-clock-call guard.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
