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
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
Registers builtin_fcfs at scheduler startup and makes it the default
job_pick_plugin, replacing the hardcoded "xce_sched_fcfs" literal in
sched_job_picker() with a fail-loud lookup through sched_resolve_job_picker().
The picker thread now branches legacy job_elect_fn plugins (delegated
unchanged, preserving their self-contained wbuf-driven loop) from native
xce_job_picker_iface_t pickers (driven by a new per-session loop), and the
allocator now calls on_dispatch/on_pend for every picker as Req 1 AC 4
requires. Closes task 2.3's flagged picker/allocator concurrency race with a
mutex on fcfs_plugin_data_t, and adds cancel points to next_job().
