From c3185d5d981a1170268f1b059bfd47464d9b39f1 Mon Sep 17 00:00:00 2001
From: Roland Tannous
Date: Mon, 9 Mar 2026 14:39:49 +0000
Subject: [PATCH 1/4] fix: allow eval-only progress events through worker
callback filter
---
studio/backend/core/training/worker.py | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/studio/backend/core/training/worker.py b/studio/backend/core/training/worker.py
index 0475152482..3941b27ab2 100644
--- a/studio/backend/core/training/worker.py
+++ b/studio/backend/core/training/worker.py
@@ -135,7 +135,9 @@ def run_training_process(
# Wire up progress callback → event_queue
def _on_progress(progress: TrainingProgress):
- if progress.step >= 0 and progress.loss > 0:
+ has_train_loss = progress.step >= 0 and progress.loss > 0
+ has_eval_loss = progress.eval_loss is not None
+ if has_train_loss or has_eval_loss:
event_queue.put({
"type": "progress",
"step": progress.step,
From 2a11e79b8bdbc17df518cf8840384ab9518d3f85 Mon Sep 17 00:00:00 2001
From: Roland Tannous
Date: Mon, 9 Mar 2026 15:35:49 +0000
Subject: [PATCH 2/4] fix: restore eval_enabled early signal for subprocess
training
---
studio/backend/core/training/training.py | 3 +++
studio/backend/core/training/worker.py | 8 ++++++++
2 files changed, 11 insertions(+)
diff --git a/studio/backend/core/training/training.py b/studio/backend/core/training/training.py
index cc0124ae83..b4d33d7c35 100644
--- a/studio/backend/core/training/training.py
+++ b/studio/backend/core/training/training.py
@@ -384,6 +384,9 @@ class TrainingBackend:
self.eval_step_history.append(step)
self.eval_enabled = True
+ elif etype == "eval_configured":
+ self.eval_enabled = True
+
elif etype == "status":
self._progress.status_message = event.get("message", "")
self._progress.is_training = True
diff --git a/studio/backend/core/training/worker.py b/studio/backend/core/training/worker.py
index 3941b27ab2..f657b1c77a 100644
--- a/studio/backend/core/training/worker.py
+++ b/studio/backend/core/training/worker.py
@@ -269,6 +269,14 @@ def run_training_process(
if eval_steps is not None and float(eval_steps) <= 0:
eval_dataset = None
+ # Tell the parent process that eval is configured so the frontend
+ # shows "Waiting for first evaluation step..." instead of "not configured"
+ if eval_dataset is not None:
+ event_queue.put({
+ "type": "eval_configured",
+ "ts": time.time(),
+ })
+
if dataset is None or trainer.should_stop:
if trainer.should_stop:
event_queue.put({"type": "complete", "output_dir": None, "ts": time.time()})
From 6eba6fff438b0c3b73fd8daf60c5207aa56da093 Mon Sep 17 00:00:00 2001
From: Roland Tannous
Date: Mon, 9 Mar 2026 16:20:00 +0000
Subject: [PATCH 3/4] fix: disable Start Training when eval_steps set without
eval split
---
.../studio/sections/training-section.tsx | 9 ++++++--
.../frontend/src/features/training/index.ts | 1 +
.../src/features/training/lib/validation.ts | 22 +++++++++++--------
3 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/studio/frontend/src/features/studio/sections/training-section.tsx b/studio/frontend/src/features/studio/sections/training-section.tsx
index 6f0297b03f..43cc2f889e 100644
--- a/studio/frontend/src/features/studio/sections/training-section.tsx
+++ b/studio/frontend/src/features/studio/sections/training-section.tsx
@@ -12,6 +12,7 @@ import {
serializeConfigToYaml,
useTrainingActions,
useTrainingConfigStore,
+ validateTrainingConfig,
} from "@/features/training";
import {
Archive04Icon,
@@ -43,7 +44,8 @@ export function TrainingSection() {
const { isStarting, startError, startTrainingRun } = useTrainingActions();
const isIncompatible =
!store.isVisionModel && store.isDatasetImage === true;
- const fileInputRef = useRef(null);
+ const configValidation = validateTrainingConfig(store);
+ const fileInputRef = useRef(null);
const handleFileUpload = (e: React.ChangeEvent) => {
const file = e.target.files?.[0];
@@ -150,7 +152,7 @@ export function TrainingSection() {
data-tour="studio-start"
className="w-full cursor-pointer bg-gradient-to-r from-emerald-500 to-teal-500 text-white hover:from-emerald-600 hover:to-teal-600"
onClick={() => void startTrainingRun()}
- disabled={isStarting || isIncompatible}
+ disabled={isStarting || isIncompatible || !configValidation.ok}
>
{isStarting ? "Starting..." : "Start Training"}
@@ -163,6 +165,9 @@ export function TrainingSection() {
Text model is not compatible with a multimodal dataset. Switch to a vision model or choose a text-only dataset.
)}
+ {!configValidation.ok && configValidation.message && !isIncompatible && (
+ {configValidation.message}
+ )}
{/* Upload / Save / Reset */}
Training Config
diff --git a/studio/frontend/src/features/training/index.ts b/studio/frontend/src/features/training/index.ts
index d2fd4f2e43..9da25f88bb 100644
--- a/studio/frontend/src/features/training/index.ts
+++ b/studio/frontend/src/features/training/index.ts
@@ -11,3 +11,4 @@ export { listLocalModels } from "./api/models-api";
export type { LocalModelInfo } from "./api/models-api";
export type { TrainingPhase } from "./types/runtime";
export { parseYamlConfig, serializeConfigToYaml } from "./lib/yaml-config";
+export { validateTrainingConfig } from "./lib/validation";
diff --git a/studio/frontend/src/features/training/lib/validation.ts b/studio/frontend/src/features/training/lib/validation.ts
index ae89cdaf51..6ca95c4b02 100644
--- a/studio/frontend/src/features/training/lib/validation.ts
+++ b/studio/frontend/src/features/training/lib/validation.ts
@@ -16,18 +16,22 @@ export function validateTrainingConfig(
if (!config.dataset) {
return { ok: false, message: "Select a Hugging Face dataset first." };
}
- return { ok: true, message: null };
- }
-
- if (config.datasetSource === "upload") {
+ } else if (config.datasetSource === "upload") {
if (!config.uploadedFile) {
return { ok: false, message: "Select a local dataset first." };
}
- return { ok: true, message: null };
+ } else {
+ return { ok: false, message: "Unsupported dataset source." };
}
- return {
- ok: false,
- message: "Unsupported dataset source.",
- };
+ // Eval steps requires an eval split to be selected
+ if (config.evalSteps > 0 && !config.datasetEvalSplit) {
+ return {
+ ok: false,
+ message:
+ "Eval Steps is set but no Eval Split is selected. Choose an Eval Split or set Eval Steps to 0.",
+ };
+ }
+
+ return { ok: true, message: null };
}
From 41351e1566fe27bc156c88c7644dd888033b145a Mon Sep 17 00:00:00 2001
From: Roland Tannous
Date: Mon, 9 Mar 2026 16:36:44 +0000
Subject: [PATCH 4/4] fix: split dataset 80/20 when eval split matches train
split
---
studio/backend/core/training/trainer.py | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/studio/backend/core/training/trainer.py b/studio/backend/core/training/trainer.py
index 22c0f34075..cfc04e572e 100644
--- a/studio/backend/core/training/trainer.py
+++ b/studio/backend/core/training/trainer.py
@@ -1868,7 +1868,8 @@ class UnslothTrainer:
# Resolve eval split from a separate HF split (explicit or auto-detected)
if eval_enabled:
- if eval_split:
+ effective_train = train_split or "train"
+ if eval_split and eval_split != effective_train:
# Explicit eval split provided - load it directly
print(f"Loading explicit eval split: '{eval_split}'\n")
eval_load_kwargs = {"path": dataset_source, "split": eval_split}
@@ -1877,6 +1878,9 @@ class UnslothTrainer:
eval_dataset = load_dataset(**eval_load_kwargs)
has_separate_eval_source = True
print(f"Loaded eval split '{eval_split}' with {len(eval_dataset)} rows\n")
+ elif eval_split and eval_split == effective_train:
+ # Same split as training — will do 80/20 split after formatting
+ print(f"Eval split '{eval_split}' is the same as train split — will split 80/20\n")
else:
# Auto-detect eval split from HF (returns a separate dataset, or None)
eval_dataset = self._auto_detect_eval_split_from_hf(