GitHub-Mirror/ollama
1
0
Fork 0
mirror of https://github.com/jmorganca/ollama synced 2025-10-06 00:32:49 +02:00
Code Issues Packages Projects Releases Wiki Activity

llm: Allow overriding flash attention setting

Browse Source 
As we automatically enable flash attention for more models, there
are likely some cases where we get it wrong. This allows setting
OLLAMA_FLASH_ATTENTION=0 to disable it, even for models that usually
have flash attention.
This commit is contained in:
Jesse Gross
2025-10-01 14:38:09 -07:00
committed by Jesse Gross
parent 05a43e078a
commit fdb109469f
3 changed files with 15 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
envconfig/config.go
View File

@@ -145,8 +145,8 @@ func Remotes() []string {
return r
}
func Bool(k string) func() bool {
return func() bool {
func BoolWithDefault(k string) func(defaultValue bool) bool {
return func(defaultValue bool) bool {
if s := Var(k); s != "" {
b, err := strconv.ParseBool(s)
if err != nil {
@@ -156,7 +156,14 @@ func Bool(k string) func() bool {
return b
}
return false
return defaultValue
}
}
func Bool(k string) func() bool {
withDefault := BoolWithDefault(k)
return func() bool {
return withDefault(false)
}
}
@@ -177,7 +184,7 @@ func LogLevel() slog.Level {
var (
// FlashAttention enables the experimental flash attention feature.
FlashAttention = Bool("OLLAMA_FLASH_ATTENTION")
FlashAttention = BoolWithDefault("OLLAMA_FLASH_ATTENTION")
// KvCacheType is the quantization type for the K/V cache.
KvCacheType = String("OLLAMA_KV_CACHE_TYPE")
// NoHistory disables readline history.
@@ -263,7 +270,7 @@ type EnvVar struct {
func AsMap() map[string]EnvVar {
ret := map[string]EnvVar{
"OLLAMA_DEBUG": {"OLLAMA_DEBUG", LogLevel(), "Show additional debug information (e.g. OLLAMA_DEBUG=1)"},
"OLLAMA_FLASH_ATTENTION": {"OLLAMA_FLASH_ATTENTION", FlashAttention(), "Enabled flash attention"},
"OLLAMA_FLASH_ATTENTION": {"OLLAMA_FLASH_ATTENTION", FlashAttention(false), "Enabled flash attention"},
"OLLAMA_KV_CACHE_TYPE": {"OLLAMA_KV_CACHE_TYPE", KvCacheType(), "Quantization type for the K/V cache (default: f16)"},
"OLLAMA_GPU_OVERHEAD": {"OLLAMA_GPU_OVERHEAD", GpuOverhead(), "Reserve a portion of VRAM per GPU (bytes)"},
"OLLAMA_HOST": {"OLLAMA_HOST", Host(), "IP Address for the ollama server (default 127.0.0.1:11434)"},

2
llm/memory.go
View File

@@ -195,7 +195,7 @@ func estimateGPULayers(gpus []discover.GpuInfo, f *ggml.GGML, projectors []strin
slog.Warn("model missing blk.0 layer size")
}
useFlashAttention := (envconfig.FlashAttention() || f.FlashAttention()) &&
useFlashAttention := envconfig.FlashAttention(f.FlashAttention()) &&
(discover.GpuInfoList)(gpus).FlashAttentionSupported() &&
f.SupportsFlashAttention()

8
llm/server.go
View File

@@ -196,14 +196,10 @@ func NewLlamaServer(gpus discover.GpuInfoList, modelPath string, f *ggml.GGML, a
loadRequest.ProjectorPath = projectors[0]
}
fa := envconfig.FlashAttention(f.FlashAttention())
// This will disable flash attention unless all GPUs on the system support it, even if we end up selecting a subset
// that can handle it.
fa := envconfig.FlashAttention()
if f.FlashAttention() {
slog.Info("model wants flash attention")
fa = true
}
if fa && !gpus.FlashAttentionSupported() {
slog.Warn("flash attention enabled but not supported by gpu")
fa = false