finetune : zero the loraB initial vectors (#4082)

* finetune : zero the loraB initial vectors

Without this, the first iteration is starting out far from the base model, instead of exactly on it.
Zeroing loraB is what the paper recommends. loralib also zeroes at least one of the init vector pairs
(though it departs from the paper in using a different distribution for the other vector, in some cases).

* tabs to spaces

* Use ggml_set_zero instead of adding a new function

diff --git a/examples/finetune/finetune.cpp b/examples/finetune/finetune.cpp
index 5a6cf22ce1b951f5ff04da2c8fcd0e24f63779f4..7fecce2541c9955f8ac9ac48e78082ceaed6d7a8 100644 (file)
--- a/examples/finetune/finetune.cpp
+++ b/examples/finetune/finetune.cpp
@@ -548,35 +548,35 @@ static void randomize_lora(struct my_llama_lora * lora, int seed, float mean, fl
     struct random_normal_distribution * rnd = init_random_normal_distribution(seed, mean, std, min, max);
 
     randomize_tensor_normal(lora->tok_embeddings_a, rnd);
-    randomize_tensor_normal(lora->tok_embeddings_b, rnd);
+    ggml_set_zero(lora->tok_embeddings_b);
     randomize_tensor_normal(lora->norm_a,           rnd);
-    randomize_tensor_normal(lora->norm_b,           rnd);
+    ggml_set_zero(lora->norm_b);
     randomize_tensor_normal(lora->output_a,         rnd);
-    randomize_tensor_normal(lora->output_b,         rnd);
+    ggml_set_zero(lora->output_b);
 
     for (uint32_t i = 0; i < n_layer; ++i) {
         auto & layer = lora->layers[i];
         randomize_tensor_normal(layer.attention_norm_a, rnd);
-        randomize_tensor_normal(layer.attention_norm_b, rnd);
+        ggml_set_zero(layer.attention_norm_b);
 
         randomize_tensor_normal(layer.wq_a, rnd);
-        randomize_tensor_normal(layer.wq_b, rnd);
+        ggml_set_zero(layer.wq_b);
         randomize_tensor_normal(layer.wk_a, rnd);
-        randomize_tensor_normal(layer.wk_b, rnd);
+        ggml_set_zero(layer.wk_b);
         randomize_tensor_normal(layer.wv_a, rnd);
-        randomize_tensor_normal(layer.wv_b, rnd);
+        ggml_set_zero(layer.wv_b);
         randomize_tensor_normal(layer.wo_a, rnd);
-        randomize_tensor_normal(layer.wo_b, rnd);
+        ggml_set_zero(layer.wo_b);
 
         randomize_tensor_normal(layer.ffn_norm_a, rnd);
-        randomize_tensor_normal(layer.ffn_norm_b, rnd);
+        ggml_set_zero(layer.ffn_norm_b);
 
         randomize_tensor_normal(layer.w1_a, rnd);
-        randomize_tensor_normal(layer.w1_b, rnd);
+        ggml_set_zero(layer.w1_b);
         randomize_tensor_normal(layer.w2_a, rnd);
-        randomize_tensor_normal(layer.w2_b, rnd);
+        ggml_set_zero(layer.w2_b);
         randomize_tensor_normal(layer.w3_a, rnd);
-        randomize_tensor_normal(layer.w3_b, rnd);
+        ggml_set_zero(layer.w3_b);
     }
 
     free_random_normal_distribution(rnd);