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Configuration Guide

Every parameter on the LoRA Optimizer, organized by what it controls. Each section explains what the parameter does, when to change it, and how it interacts with other settings.


Strength Controls

output_strength (0.0 – 10.0, default 1.0)

Master volume for the entire merge. Scales all merged patches uniformly before applying to the model.

  • Start at 1.0 and adjust if the merge is too strong/weak
  • The analysis report includes a suggested max output strength — going above this risks oversaturation
  • Does not affect the merge itself — only the final application strength

clip_strength_multiplier (0.0 – 10.0, default 1.0)

Scales CLIP (text encoder) patches relative to the model patches.

  • At 1.0, CLIP patches use the same effective strength as model patches
  • Lower values reduce text encoder influence while keeping model influence full
  • Only relevant when CLIP is connected

Merge Strategy

optimization_mode

Controls whether the optimizer picks strategies per-prefix or globally.

Value Behavior When to Use
per_prefix (default) Each weight group gets its own strategy Almost always — this is the main feature
global Single strategy for all prefixes When you want consistent behavior across all layers
weighted_sum_only Force weighted sum everywhere For distillation/edit LoRAs, or when combined with SVD compression for zero-loss output

behavior_profile

Controls which merge strategies are available during auto-selection. This is about strategy logic — which algorithms can be picked.

Value Auto-selectable Strategies When to Use
v1.2 (default) TIES, weighted_average, SLERP, consensus Recommended — full algorithm repertoire
no_slerp TIES, weighted_average, consensus If SLERP produces undesirable results for your LoRAs
classic TIES, weighted_average only Reproduce pre-1.2 behavior

architecture_preset

Tunes numeric thresholds (density ranges, noise floors, strength caps) to match the model family. This is about numbers — independent of which strategies are available.

Value Models Effect
auto (default) Auto-detected Picks the right preset from LoRA key patterns
sd_unet SD 1.5, SDXL Lower density floor (0.1), 10% noise floor, max strength 3.0
dit Flux, Wan, Z-Image, LTX, HunyuanVideo Higher density floor (0.4), 5% noise floor, max strength 5.0
llm Qwen, LLaMA Tight density range (0.1–0.8), 15% noise floor, max strength 3.0

Generally leave this on auto. Override only if auto-detection picks the wrong family.

merge_strategy_override (optional input)

Forces a specific merge strategy, bypassing all auto-selection. Connect the merge_strategy output from the Conflict Editor node, or type one of: auto, ties, consensus, slerp, weighted_average, weighted_sum.


Auto-Strength

auto_strength (enabled / disabled)

When enabled, reduces all LoRA strengths proportionally to prevent oversaturation. Uses interference-aware energy normalization — accounts for the actual directional alignment between LoRAs, not just their magnitudes.

Scenario Effect
Enabled, 2 aligned LoRAs ~50% strength each (they reinforce)
Enabled, 2 orthogonal LoRAs ~71% strength each (independent)
Enabled, 2 opposing LoRAs ~100% each (they cancel)
Disabled Strengths used as-is

Recommendation: Enable when stacking 2+ LoRAs at full strength, especially on distilled/turbo models. The Simple optimizer variant enables this by default.


Sparsification

sparsification

Zeroes out a fraction of each LoRA's weights before merging to reduce interference.

Value Method Best For
disabled (default) No sparsification When LoRAs don't interfere much
dare Random mask, rescale survivors General purpose denoising
della Magnitude-aware mask (keeps important weights) More surgical than DARE
dare_conflict DARE only at positions where LoRAs disagree Preserve unique features while reducing interference
della_conflict DELLA only at conflict positions Best of both: surgical + targeted

Interaction with TIES: When TIES is the merge strategy, sparsification replaces the TIES trim step. When using other strategies, sparsification runs as preprocessing.

sparsification_density (0.01 – 1.0, default 0.7)

Fraction of parameters to keep. Lower = more aggressive sparsification.

  • 0.9 → keep 90%, drop 10% (gentle)
  • 0.7 → keep 70%, drop 30% (moderate, default)
  • 0.5 → keep 50%, drop 50% (aggressive)

dare_dampening (0.0 – 1.0, default 0.0)

DAREx-q enhancement for DARE modes only. Interpolates the rescaling factor toward 1.0.

  • 0.0 → standard DARE rescaling (1/density)
  • Higher → less noise amplification, slightly biased magnitudes
  • Only affects dare and dare_conflict modes

Merge Quality

merge_quality

Controls additional processing techniques applied during merging. Higher quality = better conflict resolution at slight compute cost.

Level Techniques Added Cost
standard (default) Element-wise sign voting only Baseline
enhanced + DO-orthogonalization, column-wise voting, TALL-mask protection Minimal extra compute, no extra VRAM
maximum + KnOTS SVD alignment (on top of enhanced) More VRAM for SVD decomposition

Recommendations:

  • Start with standard — it's often sufficient
  • Try enhanced if you see artifacts or loss of individual LoRA character
  • Use maximum for critical merges where quality matters most
  • Best combined with conflict-aware sparsification (dare_conflict or della_conflict)

Compression & Memory

compress_patches

Re-compresses merged full-rank patches to low-rank via SVD, reducing RAM by ~32x.

Value Compresses Quality Loss
non_ties (default) weighted_sum and weighted_average prefixes None (linear ops are exactly representable)
all All prefixes including TIES Lossy on TIES prefixes (nonlinear ops produce full-rank)
disabled Nothing None, but ~32x more RAM

svd_device (gpu / cpu)

Device for SVD compression. GPU is 10–50x faster. Use CPU only if GPU memory is tight.

cache_patches (enabled / disabled)

When enabled, keeps merged patches in RAM between executions. Same LoRA stack + same settings = instant re-execution. Disable for video models or when RAM is constrained.

free_vram_between_passes (enabled / disabled)

Releases GPU cache between Pass 1 (analysis) and Pass 2 (merge). Negligible speed cost, slight VRAM reduction.

vram_budget (0.0 – 1.0, default 0.0)

Fraction of free VRAM to use for keeping merged patches on GPU.

  • 0.0 → all patches on CPU (default, safest)
  • 0.5 → use up to 50% of available free VRAM for patches
  • 1.0 → use all available free VRAM

Higher values = faster sampling (less CPU→GPU transfer) but more GPU memory used. Available on both the Optimizer and AutoTuner.


Key Normalization

normalize_keys (enabled / disabled)

Auto-detects model architecture and remaps LoRA keys to a canonical format, enabling correct merge across different trainers.

When to Enable When to Leave Disabled
Mixing LoRAs from different trainers All LoRAs from the same trainer
Using Z-Image LoRAs with fused QKV Single-trainer workflows
WanVideo LoRAs (enabled by default on WanVideo Optimizer) When auto-detection picks the wrong architecture

Supported architectures: FLUX, SDXL, Z-Image (Lumina2), Wan 2.1/2.2, LTX Video, Qwen-Image.


AutoTuner-Specific

top_n (1 – 10, default 3)

Number of candidate configurations to actually merge and score in Phase 2. Higher = more thorough but slower.

  • 3 → good balance of speed and coverage
  • 5–10 → more alternatives to choose from via Merge Selector
  • 1 → fastest, but no alternatives

scoring_svd (enabled / disabled)

When enabled, computes SVD-based effective rank as part of the quality score. More thorough but slower.

scoring_device (cpu / gpu)

Device for SVD scoring computations. GPU is 10–50x faster than CPU.

record_dataset (enabled / disabled)

Saves analysis metrics and scoring results to lora_optimizer_reports/autotuner_dataset.jsonl. Used for threshold tuning research — not needed for normal use.


Simple 2-LoRA Merge (Quick)

Use the LoRA Optimizer (Simple) node. Everything is handled automatically.

High-Quality Multi-LoRA Merge

Parameter Value
auto_strength enabled
optimization_mode per_prefix
merge_quality enhanced
sparsification della_conflict
sparsification_density 0.7
compress_patches non_ties

Maximum Quality (Critical Merge)

Parameter Value
auto_strength enabled
optimization_mode per_prefix
merge_quality maximum
sparsification della_conflict
sparsification_density 0.7
compress_patches non_ties

Video Models (Low Memory)

Parameter Value
cache_patches disabled
compress_patches all
free_vram_between_passes enabled
normalize_keys enabled
vram_budget 0.0

Let the AutoTuner Decide

Use the LoRA AutoTuner node with top_n=5. Review the report, then use Merge Selector to try alternatives.