* Replace standalone Studio wording with Unsloth
Replace the single word Studio with Unsloth wherever it is used as
shorthand for Unsloth Studio in docs, CLI output, UI strings, i18n
locales, workflow display names, comments and docstrings.
Kept unchanged: the full name Unsloth Studio, third party product
names (LM Studio, Visual Studio, Mac Studio), feature names
(Recipe Studio, Fine-tuning Studio and its translations), and all
identifiers such as env vars, commands, paths and filenames.
* Address review feedback on the Studio wording rename
Use "an" before Unsloth where the rename left the article as "a".
Restore the split brand where Unsloth and Studio render as two halves
of the full product name: the onboarding sidebar subtitle and the
IPv6 localhost warning. Scope two messages to the full name Unsloth
Studio where plain Unsloth was misleading: the AMD README bullet and
the CLI studio setup error.
* Studio: offer the latest transformers release for brand-new architectures
When a model's config.json model_type is absent from every installed
transformers overlay (base 4.57.x and the .venv_t5_530/550/510 sidecars),
Studio now checks, unauthenticated and cached, whether the newest
transformers ships it:
- utils/transformers_latest.py fetches the latest release version from
https://pypi.org/pypi/transformers/json and the CONFIG_MAPPING_NAMES
sources for that tag and for main from raw.githubusercontent.com
(never api.github.com), parsing them with the same AST extractor the
static router uses (no code execution, no trust_remote_code). Results
are cached in memory and in a JSON snapshot under studio_root()/cache
with a one day ttl; fetches are bounded to 5s with one retry and a
failure backoff, and offline mode or the new kill switch
UNSLOTH_STUDIO_NO_LATEST_TRANSFORMERS=1 short-circuits to None.
- POST /api/inference/validate gains requires_transformers_upgrade plus
a transformers_upgrade payload (model_type, pypi_version,
supported_in_pypi, supported_in_main) so the frontend can raise the
install consent dialog before /load, mirroring the existing
remote-code consent flow. The check fires only when the model_type is
unknown to all installed overlays and the hardcoded tier tables.
- POST /api/inference/install-latest-transformers provisions a new
persistent .venv_t5_latest sidecar after user consent, pinned to the
exact PyPI version (re-verified server-side) with the same
--target/--no-deps recipe as the fixed sidecars. A JSON pin marker
inside the dir records the installed package set, so restarts
revalidate it and routing resolves the new highest-ranked tier
automatically. A dependency preflight (compat_plan) compares the
release's requires_dist against the running env: unsatisfied
tokenizers/safetensors floors are shadow-installed as exact pins into
the sidecar, anything else unsatisfied blocks the install with a
clear message.
Routing for every already-supported model_type is unchanged: the
hardcoded lists and the 530/550/510 static resolver run first, the new
tier only participates once its venv exists, and the probe order gains
the latest sidecar only when provisioned. Verified against live PyPI
and GitHub (transformers 5.13.0: 674 model_types, 26 absent from all
installed overlays, e.g. cosmos3_omni; 4 dev-only on main) and with a
real sidecar install plus restart persistence. 64 new tests; the
existing 200-test transformers_version suite passes unchanged.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Latest-transformers check: fetch outside the lock, serialize installs
Release the module lock during the network refresh so a slow fetch cannot
stall other threads in the ASGI pool; concurrent callers during a fetch get
None (the graceful fallthrough) via an in-flight flag instead of stacking
fetches. Serialize install_latest_transformers with an in-progress flag so
concurrent consents cannot race the sidecar delete and recreate; the loser
gets a structured already-in-progress refusal.
* Latest-transformers check: LoRA bases, pin-gated mapping, live reverify
Run the upgrade check over the [adapter, base] target set so a LoRA whose
base model is a brand-new architecture surfaces the prompt (the worker
activates transformers for the base, not the adapter).
Gate the latest overlay's mapping lookup on a valid pin marker, matching
activation and the probe order, so a partial or manual .venv_t5_latest dir
cannot be routed to and then refused at activation.
Re-verify the requested version against a live PyPI snapshot at install
time, falling back to the cached one on fetch failure, so a release
published inside the cache TTL is not silently missed.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Latest-transformers check: nested config types and latest-tier vision probe
Collect every model_type in the config (top level plus each nested
sub-config) and signal on the first one missing from all installed
overlays, so a supported wrapper carrying a brand-new backbone still
surfaces the upgrade prompt; wrappers instantiate sub-configs through
CONFIG_MAPPING and would fail on the nested type.
Route the vision capability subprocess through the pinned latest sidecar
when the model resolves to the latest tier, so latest-only VLMs are not
misclassified as text-only; every other tier keeps the 5.5 sidecar used
today.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Latest tier: nested routing, vision probe after raw miss, safe upgrades
Route by every model_type in the config: a nested sub-config type can raise
the tier (wrappers instantiate sub-configs through CONFIG_MAPPING), so a
supported wrapper with a latest-only backbone routes to latest once
installed instead of staying on default. An unknown nested type never
vetoes; the primary type keeps its previous semantics. The collector is
shared with the upgrade checker.
Vision detection: when the raw heuristics say False for a model that routes
to the latest tier, run the AutoConfig subprocess under the pinned latest
sidecar instead of trusting heuristics built from older transformers.
Provisioning: stage-and-swap. Build the new sidecar in .venv_t5_latest.staging
and swap it in only when the install and pin marker are complete, so a failed
upgrade never destroys a previously working sidecar; restore the old dir if
the final swap fails.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Latest-transformers checker, vision subprocess, and cache fixes
Require the latest release to support every missing model_type (the
primary included) before prompting; a nested-only match cannot make the
model loadable, so no install is offered for it.
The vision-check subprocess now unions the active sidecar's own
registry mappings into the inlined parent-process detection sets, so
architectures only the sidecar knows classify correctly.
A successful sidecar install clears the tier probe cache, the latest
tier's model_type mapping, and the vision-detection cache so the new
venv takes effect without a restart. Tests for all three.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Aggregate upgrade support flags and keep install off /v1
The upgrade signal now reports supported_in_pypi only when the latest
release covers every missing model_type; a mix with a main-only nested
type surfaces as dev-only so no PyPI install is offered that would
still fail at load. The consented install endpoint moves to
studio_router so it is not reachable through the OpenAI-compatible /v1
mount. Tests for both.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Honor the latest-transformers kill switch in routing
With UNSLOTH_STUDIO_NO_LATEST_TRANSFORMERS set after the sidecar was
provisioned, the latest tier still joined mapping and probe routing
because only the pin was checked. Both admission points now also check
the kill switch, so operators can roll back a problematic sidecar
without deleting files.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Repair the latest sidecar through stage-and-swap
The lazy repair path installed into the live .venv_t5_latest, which
_ensure_venv_dir wipes first, so a failed repair deleted the pinned
sidecar and its marker. Both the consented install and the repair now
share one stage-and-swap helper: the incomplete-but-pinned dir survives
any failure and a later attempt can still repair it.
* Tighten comments
* Remove the staging dir when a latest-sidecar install fails
A pip failure inside _ensure_venv_dir returns False without raising, so
the except cleanup never ran and the partial .venv_t5_latest.staging
leaked until a later attempt. Also note on the validate response fields
that frontend consumption ships in the follow-up PR.
* Add the transformers-upgrade consent dialog to the frontend
When /validate reports requires_transformers_upgrade, every explicit load
path (chat runtime and the compare composer) now pauses on a consent
dialog modeled on the remote-code one: it names the model_type and the
latest PyPI transformers version, and on Accept calls
/api/inference/install-latest-transformers itself, shows an installing
state, and resumes the original load automatically on success. Errors
surface in the dialog with a retry; Cancel aborts the load like the
trust dialog's deny path. Architectures shipped only on transformers
main get a dev-only notice with no install button. Background auto-load
skips upgrade-requiring candidates instead of prompting, mirroring the
trust_remote_code rule. The dialog mounts once in the root layout and
runs before the security dialogs, since no load can proceed without the
runtime.
* Route a non-installable new architecture to the custom-code consent as a last resort
When the upgrade dialog has no installable PyPI release (the architecture
is only on transformers main, which Studio never installs), the dialog now
says so explicitly, and when the model also declares custom (auto_map)
code it offers Continue with custom code: resolving the paused load into
the existing trust_remote_code consent gate instead of hard-aborting.
Models with no custom code keep the Cancel-only notice. The backend
returns no upgrade signal at all for architectures unknown to both PyPI
and main, so those still route straight to the unchanged security gate.
* Force a 16-bit load for models on the latest-transformers sidecar
Live validation with Zyphra/ZAYA1-8B (model_type zaya, shipped by
transformers 5.13.1 but unknown to every installed tier) surfaced a
generation crash when the consented sidecar load kept the default bnb
4-bit quantization: transformers' grouped-MoE kernels feed the packed
uint8 expert weights straight into torch._grouped_mm, and generation
dies (plain 16-bit works). New latest_tier_active_for() mirrors the
sidecar activation's tier resolution and never raises; the inference
worker flips load_in_4bit off when it reports true, and the load route
applies the same flip so the pre-load VRAM guard and the worker command
agree. Fixed tiers are untouched. With the guard, ZAYA1-8B loads and
generates correctly in Studio chat.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Offer the custom-code fallback when a latest-sidecar install fails
* Fail remote mapping fetches wholesale and mirror the 16-bit flip in validate
A transient fetch or parse failure of one auto-mapping file no longer caches
a partial latest-release map for the TTL (a real 404 on pre-5.10 tags is
still tolerated), and validate_model now applies the same latest-sidecar
16-bit sizing flip as /load before the training guard so the two agree.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Tighten comments in the latest-transformers changes
* Resolve remote LoRA bases, fold nested tiers, and guard the sidecar swap
latest_tier_active_for now resolves a remote adapter's base model the same
way worker pre-activation does (and returns early without a sidecar pin), a
hardcoded fast-path tier is raised when a nested sub-config's model_type
needs a higher sidecar, and the install route refuses to swap .venv_t5_latest
while training runs on it and unloads a latest-tier chat model first.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Gate the sidecar install on worker liveness and size installable upgrades 16-bit
The install route now refuses while any training or export runs (tier
re-resolution without the load token is unreliable for gated repos), holds
the inference lifecycle gate across the unload and the swap so no load can
interleave, and passes the model name to unload_model. validate_model runs
the upgrade check before the training guard and sizes an installable
upgrade as 16-bit, matching what /load and the worker will force after the
consented install.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Close the sidecar install races and honor the kill switch over cached mappings
Training starts and mutating export routes now refuse while a transformers
install is in progress (shared is_install_in_progress flag), the chat unload
and idle export-worker teardown moved into a before_swap hook that runs only
once the staged install succeeded, and _config_model_types checks the kill
switch before returning a cached latest mapping.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Reserve the sidecar swap before the gate wait and abort it on failed teardown
The install-in-progress flag moved into a shared sidecar swap reservation in
transformers_version, taken by the install route before awaiting the
inference lifecycle gate (so training and export starts see it for the whole
window) and by the lazy .venv_t5_latest repair path. The before_swap hook
now raises when the chat unload or export teardown reports failure, leaving
the previous sidecar untouched.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Back the sidecar swap reservation with a cross-process lock file
The lazy repair runs inside worker subprocesses, where a module-level flag
is invisible to the parent's route checks. The reservation now also creates
a lock file next to .venv_t5_latest (O_EXCL, owner-only removal, stale after
two hours for crashed owners), so is_install_in_progress sees a repair from
any Studio process.
* Hand the swap reservation to the installer thread and harden pre-swap teardown
A cancelled install request no longer releases the reservation while the
installer thread is still staging (the thread owns and releases it, shielded
from cancellation). The route refuses while another inference request is
generating, export teardown runs before the chat unload and is judged by
worker liveness rather than the cleanup return value, and a live inference
worker with no active model (failed load residue) is shut down before the
swap.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Keep the lifecycle gate with the installer and recheck the swap at spawn time
The gate moved into the shielded install task so a cancelled POST cannot
release the guard /load honors while the installer still runs, cached latest
probe results are ignored while the kill switch is set, and the training and
export subprocess spawns recheck the sidecar swap reservation right before
spawning (the route-level guards are one-shot and validation can outlast an
install's start).
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Close the spawn-registration windows against the sidecar install
Training marks the spawn in progress before its reservation recheck and
is_training_active honors the flag, so the install route sees a start that
has passed proc.start() but not yet recorded _proc. Export load-checkpoint
rechecks the reservation after setting _export_active and before tearing
down the old worker, so losing the race keeps the loaded checkpoint instead
of surfacing a 500.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Refine the install-window interleavings around worker teardown
The inference busy count is rechecked under the lifecycle gate (streams
start by taking that gate, so nothing slips past a held gate), the training
handshake moved ahead of the VRAM-freeing before_spawn hook so a lost race
leaves chat/export intact, the export spawn-time check is op-aware (inside
an active op the install is the side that aborts), and the Xet-stall respawn
waits out a transient reservation instead of stranding the run.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Track the install's server-side unload and guard export ops against the swap
The upgrade dialog store records when its install actually ran (the server
unloads the active chat model before swapping), and the load flow then marks
the previous model as unloaded so a later cancelled gate still triggers
rollback; the custom-code fallback leaves the flag unset. _run_export gained
the same reservation handshake as load_checkpoint so an install cannot block
behind an hours-long export op instead of returning 409.
* Tighten comments in the install-guard and upgrade-consent changes
* Surface install-race refusals cleanly and roll back after a failed swap unload
/load refuses while the sidecar swap is reserved so a load cannot succeed
and immediately be unloaded by the pre-swap teardown, worker starts that
lose the install race raise a typed SidecarSwapInProgress mapped to 409
instead of a 500, the install response reports model_unloaded even on a
structured failure so the client can restore its state, and the compare
flow tracks the server-side unload like the primary load path and clears a
stale checkpoint on abort.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Type the export install races, scope the lock release, and keep the unload signal
Export load-checkpoint and export ops raise SidecarSwapInProgress (mapped to
409 in every export route) instead of a 400-shaped failure, the export spawn
check distinguishes repair reservations (always refused) from install ones
(op-aware), the swap lock release only unlinks a lock this process wrote so
a stale-superseded owner cannot drop the new owner's live lock, and the
frontend unload signal survives a superseding consent via read-and-clear
consumption instead of a reset.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Finalize a stalled run when the respawn loses the install race and latch the unload signal
The Xet-stall respawn timeout now finalizes the run as a failure instead of
raising into the pump's broad finalization catch (which stranded it in a
training state with no worker), and a successful install retry ORs the
model_unloaded signal with the latched value so a failed-after-unload first
attempt still triggers rollback.
* Recheck the swap under the load gate and latch the unload before resolver checks
/load rechecks the sidecar reservation after acquiring the lifecycle gate
(an install can reserve while the load queues on it), and the dialog store
latches model_unloaded as soon as the install response arrives, before any
resolver-identity guard, so a superseded consent's unload still reaches
whichever load consumes the signal next.
* Report cleared-state unload failures, guard queued installs, and fold name tiers
A failed chat unload that still cleared the orchestrator's model state now
reports model_unloaded so the client rolls back, the installer aborts with
a 409 when a model load completed while it waited on the lifecycle gate,
and the fixed-tier name fast path consults the config mapping when a latest
sidecar is pinned so an accepted upgrade routes to the sidecar it installed
(no I/O added to the unpinned path).
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Report cleared-state unload failures and harden the spawn handshake flag
The failed-unload branch in before_swap now detects that the orchestrator
cleared its model state and reports model_unloaded before aborting (the
earlier commit claimed this fix but a scripting error dropped the edit),
the installer's queued-load check compares a load generation counter so a
same-model reload is caught, and both training spawn sites wrap everything
after the handshake in a guard that resets _spawn_in_progress on any
exception so a failed start cannot wedge is_training_active.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Bump the load generation when the load is published, not at load start
A start-time bump is already visible when the installer snapshots mid-load,
so a same-model reload completing after the snapshot looked unchanged and
could be unloaded by the swap. The counter now increments alongside the
active_model_name publish.
* Self-heal a broken pinned sidecar, guard lazy repairs, and refresh stale retries
A valid pin whose transformers source dir vanished now triggers the repair
from the routing path (with a five minute backoff after failures) instead of
silently routing latest-only models to older tiers, the lazy repair refuses
while parent-visible chat/training/export workers are active since it has no
teardown of its own, and a version-mismatch install failure carries the
superseding release so the dialog's Retry re-requests a version that can
succeed.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Flip latest-tier loads to 16-bit outside chat and protect export state
Training and export workers now apply the same latest-sidecar 16-bit flip
as the chat worker so a brand-new grouped-MoE architecture cannot reach bnb
4-bit through those paths, the latest-tier vision override returns None on
an inconclusive probe so a transient failure is not cached as not-vision,
and the install route refuses while an idle export checkpoint is loaded
rather than discard it with no rollback signal on a failed swap.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Address parallel-review findings on the sidecar guards and install checks
The training route sizes latest-tier jobs 16-bit before GPU selection, the
inference subprocess spawn rechecks the swap reservation like training and
export (covering the OpenAI auto-switch path) with the typed error mapped
to a retryable 409, compat_plan blocks the install when dependency metadata
cannot be fetched instead of proceeding unverified, snapshot model-type
lists must contain only strings, and pin-marker package specs are validated
against the sidecar's own package set before ever reaching pip.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Parent-only repairs, live-owner locks, remote-base activation, pre-teardown recheck
Lazy sidecar repairs now refuse inside worker children (whose empty backend
singletons cannot see live siblings) and run only in the parent where the
active-worker guard is real, swap-lock staleness requires the owner pid to
be dead so a slow live install is never superseded, both activation entry
points resolve a remote adapter's base model like the inference worker and
latest_tier_active_for already do, and load_model rechecks the reservation
before tearing down the old worker so losing the race keeps the current
model loaded.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Check workers under the repair reservation and keep state on refused swaps
The lazy repair now reserves first and checks workers under the reservation
(worker starts set their active markers before rechecking, so every
interleaving aborts one side), with export ops and in-flight inference loads
counted as active. The inference pre-teardown and spawn guards refuse only
repair reservations since an install shares the load's lifecycle gate and
aborts via its queued-load snapshot, a SidecarSwapInProgress raised before
teardown no longer clears the live model mirrors, and an export spawn abort
after teardown clears current_checkpoint so the page cannot claim a loaded
checkpoint with no worker.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
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* Repair a present-but-incomplete latest sidecar from routing
The routing self-heal only fired when the pinned sidecar's transformers/
dir was missing. A sidecar that kept transformers/ but lost another pinned
package still routed models to the latest tier, and workers refuse
parent-only repairs, so every load failed until a manual reinstall. Routing
now validates the full pin (via _venv_dir_is_valid) and repairs any
incomplete sidecar under the same swap reservation and 5-minute backoff.
* Treat an unrepaired latest sidecar as unavailable in routing
When the pinned sidecar is incomplete and the lazy repair fails (offline,
pip failure, workers active) or is inside the backoff window, routing
returned the source dir anyway, sending models to a tier whose worker
activation is known to fail. Return None instead so models an older tier
supports keep loading there until a repair succeeds, matching the behavior
when the sidecar dir is missing entirely.
* Harden sidecar swap and repair against crash, survivor, and 16-bit paths
Reclaim a swap lock as soon as its recorded owner PID is dead instead of
waiting out the two-hour cutoff, so a crash mid-install no longer wedges
/load, training, export, and repair for hours. A lock whose PID cannot be
read yet still uses the long cutoff so the create-before-write window is
never mistaken for dead.
Probe process liveness with OpenProcess on Windows: os.kill(pid, 0) there
is CTRL_C_EVENT (a real Ctrl+C via GenerateConsoleCtrlEvent), not a
harmless check, and psutil is not always present.
Return whether _shutdown_subprocess actually killed the worker and keep the
live handle when it survives terminate/kill (an uninterruptible CUDA
syscall can outlive SIGKILL). The pre-swap liveness guard now trusts that
result, so the destructive .venv_t5_latest rename cannot proceed while a
live worker still holds sidecar modules.
Recover a sidecar stranded at .old when a swap's activation rename and its
rollback both fail: reading the pin restores it when no swap holds the
reservation, so latest-tier models are not permanently broken.
Resolve the latest tier in the parent for export loads and for explicitly
16-bit training runs, not only 4-bit ones: tier resolution self-heals an
incomplete sidecar, and repairs are parent-only, so those paths could not
recover before. Sidecar integrity and quantization are independent.
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* Revert the parent-side latest-tier repair probe on training and export loads
The probe ran before the route freed VRAM, so a resident chat or export worker
made _workers_active_for_repair() refuse the parent-only repair; the route then
tore that worker down and spawned a child that also cannot repair, so an
incomplete sidecar still failed to load. Repairing correctly requires running the
repair between the worker teardown and the child spawn, decoupled from VRAM
sizing, which is a larger change tracked separately. Restore the prior behavior
so these paths match the reviewed form and do not partially attempt a repair that
cannot complete while workers are resident.
* Honor failed worker shutdowns on load and revalidate the cached latest mapping
The fresh-load paths spawned a new worker straight after _shutdown_subprocess
without checking its result, so a worker that outlived terminate/kill (a wedged
CUDA syscall) had its handle overwritten by the replacement while it still held
GPU memory, and is_worker_alive/the pre-swap guard could no longer see it. Both
the inference load and the export checkpoint load now abort when the old worker
did not exit, so the load can be retried once it does.
_config_model_types returned a cached latest mapping without re-checking the
sidecar, so a sidecar deleted or broken in-process after its first parse was
never re-validated: routing kept sending latest-only models to the stale latest
tier while activation failed. The cached latest mapping is now dropped and
re-resolved (self-healing) when the sidecar is no longer intact.
* Drop cached latest mapping when the pin is gone; keep 4-bit for custom-code fallback
_latest_sidecar_intact now returns False when the pin marker itself is gone, not
just when a pinned package is missing. Otherwise a cached latest mapping outlived
a deleted pin: _config_model_types kept returning it, so routing sent latest-only
models to a tier whose worker activation then failed (no pinned version) until
restart. It now drops the cache and re-resolves to no latest tier. The
_overlay_transformers_dir caller already gates on a present pin, so it is
unaffected.
validate_model forced 16-bit sizing whenever a PyPI upgrade was merely offered,
even for a model that can fall back to its own auto_map code. /load loads such a
model 4-bit without the install, and the install route refuses while training is
active, so 16-bit sizing here returned a VRAM 409 for the only viable 4-bit path.
The offered-upgrade flip is now gated on the absence of a custom-code fallback;
an already-active latest sidecar still always sizes 16-bit.
---------
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>