Browse Source

refactor kv estimation

Michael Yang 6 months ago
parent
commit
d07cf41a97
2 changed files with 20 additions and 8 deletions
  1. 16 1
      llm/ggml.go
  2. 4 7
      llm/memory.go

+ 16 - 1
llm/ggml.go

@@ -360,7 +360,7 @@ func DecodeGGML(rs io.ReadSeeker, maxArraySize int) (*GGML, int64, error) {
 	}, offset, nil
 }
 
-func (llm GGML) GraphSize(context, batch uint64) (partialOffload, fullOffload uint64) {
+func (llm GGML) GraphSize(context, batch uint64) (kv, partialOffload, fullOffload uint64) {
 	embedding := llm.KV().EmbeddingLength()
 	heads := llm.KV().HeadCount()
 	headsKV := llm.KV().HeadCountKV()
@@ -368,9 +368,12 @@ func (llm GGML) GraphSize(context, batch uint64) (partialOffload, fullOffload ui
 
 	embeddingHeads := llm.KV().EmbeddingHeadCount()
 	embeddingHeadsK := llm.KV().EmbeddingHeadCountK()
+	embeddingHeadsV := llm.KV().EmbeddingHeadCountV()
 
 	layers := llm.Tensors().Layers()
 
+	kv = 2 * context * llm.KV().BlockCount() * (embeddingHeadsK + embeddingHeadsV) * headsKV
+
 	switch llm.KV().Architecture() {
 	case "llama":
 		fullOffload = max(
@@ -403,6 +406,18 @@ func (llm GGML) GraphSize(context, batch uint64) (partialOffload, fullOffload ui
 	case "mllama":
 		var visionTokens, tiles uint64 = 1601, 4
 
+		if crossAttentionLayers, ok := llm.KV()["mllama.attention.cross_attention_layers"].(*array); ok {
+			kv = headsKV *
+				(embeddingHeadsK + embeddingHeadsV) * // one for K, one for V
+				(2* // sizeof(float16)
+					(llm.KV().BlockCount()-uint64(crossAttentionLayers.size))* // num non-cross attention layers
+					context +
+					4* // sizeof(float32)
+						uint64(crossAttentionLayers.size)* // num cross attention layers
+						visionTokens*
+						tiles)
+		}
+
 		fullOffload = max(
 			4*batch*(2+3*embedding+embeddingHeadsK*heads+context*(1+heads)),
 			// vocab graph

+ 4 - 7
llm/memory.go

@@ -123,13 +123,7 @@ func EstimateGPULayers(gpus []discover.GpuInfo, ggml *GGML, projectors []string,
 		slog.Warn("model missing blk.0 layer size")
 	}
 
-	// fp16 k,v = sizeof(float16) * n_ctx * n_layer * (n_embd_head_k + n_embd_head_v) * n_head_kv
-	var kv uint64 = 2 * uint64(opts.NumCtx) * ggml.KV().BlockCount() * (ggml.KV().EmbeddingHeadCountK() + ggml.KV().EmbeddingHeadCountV()) * ggml.KV().HeadCountKV()
-
-	// KV is proportional to the number of layers
-	layerSize += kv / ggml.KV().BlockCount()
-
-	graphPartialOffload, graphFullOffload = ggml.GraphSize(uint64(opts.NumCtx), uint64(min(opts.NumCtx, opts.NumBatch)))
+	kv, graphPartialOffload, graphFullOffload := ggml.GraphSize(uint64(opts.NumCtx), uint64(min(opts.NumCtx, opts.NumBatch)))
 	if graphPartialOffload == 0 {
 		graphPartialOffload = ggml.KV().GQA() * kv / 6
 	}
@@ -137,6 +131,9 @@ func EstimateGPULayers(gpus []discover.GpuInfo, ggml *GGML, projectors []string,
 		graphFullOffload = graphPartialOffload
 	}
 
+	// KV is proportional to the number of layers
+	layerSize += kv / ggml.KV().BlockCount()
+
 	// on metal there's no partial offload overhead
 	if gpus[0].Library == "metal" {
 		graphPartialOffload = graphFullOffload