Files
LocalAI/core/config/gguf.go
LocalAI [bot] ed3b59baf1 fix(config): cap auto-derived context to fit VRAM (#10696)
When a model is imported without an explicit context_size, the GGUF
importer defaulted the model's context to its full trained window
(n_ctx_train). For long-context models (128k / 256k / 1M) that KV cache
cannot fit a consumer GPU, so the backend aborts on load (exitCode=-1)
even though the model file is perfectly fine. Reproduced live:
gemma-4-26b-a4b-it-qat-q4_0 defaulted to context=262144 and
qwythos-9b-claude-mythos-5-1m to 1048576, both aborting on a 20 GB card.

Instead of chasing the trained max, auto-derive a conservative default:
min(trainedMax, DefaultAutoContextSize=8192). A small model keeps its
trained window; a long-context model caps at 8k and users opt into more
via context_size. This cap applies always, including CPU / unknown-VRAM
hosts, so it never regresses those paths.

Per-device VRAM is used only as a DOWNWARD safety: when a per-device
ceiling is detected (xsysinfo.MinPerGPUVRAM) and even the 8k cap would
not fit it with headroom, step down through candidate contexts to the
largest that fits, floored at DefaultContextSize. When VRAM is unknown
(0) or no GPU is detected we do NOT clamp — the bug is GPU OOM and the
8k cap is already safe, so detection gaps must not shrink the window.

The footprint estimate reuses gpustack/gguf-parser-go's
EstimateLLaMACppRun at a given context with all layers offloaded, taking
the per-device NonUMA VRAM figure. The estimate and VRAM detection are
package vars so tests inject deterministic values. Explicit context_size
always wins (guessGGUFFromFile only acts when it is nil).

Assisted-by: Claude:claude-opus-4-8 [golangci-lint go-test]

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Co-authored-by: Ettore Di Giacinto <mudler@localai.io>
2026-07-06 12:53:45 +02:00

228 lines
9.3 KiB
Go

package config
import (
"context"
"github.com/mudler/LocalAI/pkg/functions"
"github.com/mudler/LocalAI/pkg/grpc"
pb "github.com/mudler/LocalAI/pkg/grpc/proto"
"github.com/mudler/LocalAI/pkg/reasoning"
"github.com/mudler/LocalAI/pkg/xsysinfo"
"github.com/mudler/xlog"
gguf "github.com/gpustack/gguf-parser-go"
"github.com/gpustack/gguf-parser-go/util/ptr"
)
// reservedNonChatModel reports whether the operator reserved this model for an
// internal primitive — the router score classifier or the PII NER
// token_classify tier. Such a model has no chat template and must not be
// given the generative-chat defaults the GGUF importer otherwise applies
// (FLAG_CHAT, jinja templating): surfacing it in chat pickers defeats the
// reservation. Operators who do want a combined model declare both usecases
// explicitly — the combination is valid.
func reservedNonChatModel(cfg *ModelConfig) bool {
return cfg.KnownUsecases != nil &&
(*cfg.KnownUsecases&(FLAG_SCORE|FLAG_TOKEN_CLASSIFY)) != 0
}
func guessGGUFFromFile(cfg *ModelConfig, f *gguf.GGUFFile, defaultCtx int) {
if defaultCtx == 0 && cfg.ContextSize == nil {
// trainedMax is the model's full trained context window (n_ctx_train).
// Defaulting a model to it unbounded is what OOMs long-context models at
// load: a 128k / 256k / 1M KV cache cannot fit a consumer GPU and the
// backend aborts (exitCode=-1). autoContextSize instead caps to a modest
// default and only steps below it when detected per-device VRAM demands.
trainedMax := int(f.EstimateLLaMACppRun().ContextSize)
if trainedMax > 0 {
cSize := autoContextSize(f, trainedMax)
cfg.ContextSize = &cSize
} else {
defaultCtx = DefaultContextSize
cfg.ContextSize = &defaultCtx
}
}
// GPU options
if cfg.Options == nil {
if xsysinfo.HasGPU("nvidia") || xsysinfo.HasGPU("amd") {
cfg.Options = []string{"gpu"}
}
}
if cfg.NGPULayers == nil {
// we assume we want to offload all layers
defaultHigh := DefaultNGPULayers
cfg.NGPULayers = &defaultHigh
}
xlog.Debug("[gguf] guessDefaultsFromFile: NGPULayers set", "NGPULayers", cfg.NGPULayers, "modelName", f.Metadata().Name)
// identify from well known templates first, otherwise use the raw jinja template
chatTemplate, found := f.Header.MetadataKV.Get("tokenizer.chat_template")
if found {
// fill jinja template
cfg.modelTemplate = chatTemplate.ValueString()
}
// Auto-enable Multi-Token Prediction (ggml-org/llama.cpp#22673) when the
// GGUF carries an embedded MTP head. Skipped silently for non-MTP models
// and when the user already configured a spec_type.
if n, ok := HasEmbeddedMTPHead(f); ok {
ApplyMTPDefaults(cfg, n)
}
// Thinking support detection is done after model load via DetectThinkingSupportFromBackend
// template estimations
if cfg.HasTemplate() {
// nothing to guess here
xlog.Debug("[gguf] guessDefaultsFromFile: template already set", "name", cfg.Name, "modelName", f.Metadata().Name)
return
}
xlog.Debug("[gguf] Model file loaded", "file", cfg.ModelFileName(), "eosTokenID", f.Tokenizer().EOSTokenID, "bosTokenID", f.Tokenizer().BOSTokenID, "modelName", f.Metadata().Name, "architecture", f.Architecture().Architecture)
// guess the name
if cfg.Name == "" {
cfg.Name = f.Metadata().Name
}
// A model the operator reserved for an internal primitive (the router
// score classifier, or the PII NER token_classify tier) is not a chat
// model: it carries no chat template and must not be painted with the
// generative-chat defaults — appending FLAG_CHAT here would fold chat
// into KnownUsecases on the next sync and surface the model in every
// chat picker. Respect the declaration.
if !reservedNonChatModel(cfg) {
// Instruct to use template from llama.cpp
cfg.TemplateConfig.UseTokenizerTemplate = true
cfg.FunctionsConfig.GrammarConfig.NoGrammar = true
cfg.Options = append(cfg.Options, "use_jinja:true")
cfg.KnownUsecaseStrings = append(cfg.KnownUsecaseStrings, "FLAG_CHAT")
}
// Apply per-model-family inference parameter defaults (temperature, top_p, etc.)
ApplyInferenceDefaults(cfg, f.Metadata().Name)
}
// DetectThinkingSupportFromBackend calls the ModelMetadata gRPC method to detect
// if the model supports thinking mode and if the template ends with a thinking start token.
// This should be called after the model is loaded.
// The results are stored in cfg.SupportsThinking and cfg.ThinkingForcedOpen.
// The backend-reported multimodal marker is also captured into cfg.MediaMarker.
func DetectThinkingSupportFromBackend(ctx context.Context, cfg *ModelConfig, backendClient grpc.Backend, modelOptions *pb.ModelOptions) {
if backendClient == nil {
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: backend client is nil, skipping detection")
return
}
if modelOptions == nil {
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: model options is nil, skipping detection")
return
}
// Only llama-cpp exposes ModelMetadata today. Other backends will either error
// or return an empty response — both are fine, we just bail before calling.
if cfg.Backend != "llama-cpp" {
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: skipping detection", "backend", cfg.Backend)
return
}
metadata, err := backendClient.ModelMetadata(ctx, modelOptions)
if err != nil {
xlog.Warn("[gguf] DetectThinkingSupportFromBackend: failed to get model metadata", "error", err)
return
}
if metadata != nil {
// The multimodal media marker is backend-controlled (llama.cpp may pick a
// random per-server string). Empty means "no mtmd context" — Go falls back
// to templates.DefaultMultiMediaMarker at render time.
if metadata.MediaMarker != "" {
cfg.MediaMarker = metadata.MediaMarker
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: media marker captured", "marker", metadata.MediaMarker)
}
// Thinking / tool-format detection only applies when we rely on the
// backend-side tokenizer template — otherwise the rendered-template based
// heuristics below aren't meaningful.
if !cfg.TemplateConfig.UseTokenizerTemplate {
return
}
applyDetectedThinkingConfig(cfg, metadata)
// Extract tool format markers from autoparser analysis
if tf := metadata.GetToolFormat(); tf != nil && tf.FormatType != "" {
cfg.FunctionsConfig.ToolFormatMarkers = &functions.ToolFormatMarkers{
FormatType: tf.FormatType,
SectionStart: tf.SectionStart,
SectionEnd: tf.SectionEnd,
PerCallStart: tf.PerCallStart,
PerCallEnd: tf.PerCallEnd,
FuncNamePrefix: tf.FuncNamePrefix,
FuncNameSuffix: tf.FuncNameSuffix,
FuncClose: tf.FuncClose,
ArgNamePrefix: tf.ArgNamePrefix,
ArgNameSuffix: tf.ArgNameSuffix,
ArgValuePrefix: tf.ArgValuePrefix,
ArgValueSuffix: tf.ArgValueSuffix,
ArgSeparator: tf.ArgSeparator,
ArgsStart: tf.ArgsStart,
ArgsEnd: tf.ArgsEnd,
NameField: tf.NameField,
ArgsField: tf.ArgsField,
IDField: tf.IdField,
FunNameIsKey: tf.FunNameIsKey,
ToolsArrayWrapped: tf.ToolsArrayWrapped,
FunctionField: tf.FunctionField,
ParameterOrder: tf.ParameterOrder,
GenIDField: tf.GenIdField,
CallIDPosition: tf.CallIdPosition,
CallIDPrefix: tf.CallIdPrefix,
CallIDSuffix: tf.CallIdSuffix,
ReasoningStart: tf.ReasoningStart,
ReasoningEnd: tf.ReasoningEnd,
ContentStart: tf.ContentStart,
ContentEnd: tf.ContentEnd,
}
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: tool format markers detected",
"format_type", tf.FormatType,
"section_start", tf.SectionStart,
"func_name_prefix", tf.FuncNamePrefix)
}
}
}
func applyDetectedThinkingConfig(cfg *ModelConfig, metadata *pb.ModelMetadataResponse) {
if cfg == nil || metadata == nil {
return
}
// Respect explicit YAML/user config. Backend probing should only fill defaults
// when the reasoning mode has not already been set.
if cfg.ReasoningConfig.DisableReasoning == nil {
cfg.ReasoningConfig.DisableReasoning = ptr.To(!metadata.SupportsThinking)
}
// Respect explicit prefill config for the same reason. Only infer the
// default prefill behavior when the user did not set it.
if cfg.ReasoningConfig.DisableReasoningTagPrefill == nil {
// Use the rendered template to detect if thinking token is at the end.
// This reuses the existing DetectThinkingStartToken function.
if metadata.RenderedTemplate != "" {
thinkingStartToken := reasoning.DetectThinkingStartToken(metadata.RenderedTemplate, &cfg.ReasoningConfig)
thinkingForcedOpen := thinkingStartToken != ""
cfg.ReasoningConfig.DisableReasoningTagPrefill = ptr.To(!thinkingForcedOpen)
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: thinking support detected", "supports_thinking", metadata.SupportsThinking, "thinking_forced_open", thinkingForcedOpen, "thinking_start_token", thinkingStartToken)
} else {
cfg.ReasoningConfig.DisableReasoningTagPrefill = ptr.To(true)
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: thinking support detected", "supports_thinking", metadata.SupportsThinking, "thinking_forced_open", false)
}
return
}
xlog.Debug("[gguf] DetectThinkingSupportFromBackend: preserving explicit reasoning config", "supports_thinking", metadata.SupportsThinking, "disable_reasoning", *cfg.ReasoningConfig.DisableReasoning, "disable_reasoning_tag_prefill", *cfg.ReasoningConfig.DisableReasoningTagPrefill)
}