Internal change

PiperOrigin-RevId: 794620076

gemma/configs.cc

@@ -471,6 +471,37 @@ static ModelConfig ConfigGemma3_27B() {
   return config;
 }
 
+static LayerConfig LayerConfigGemma3_270M_LM(size_t model_dim) {
+  LayerConfig config;
+  config.model_dim = model_dim;
+  config.ff_hidden_dim = 2048;
+  config.heads = 4;
+  config.kv_heads = 1;
+  config.qkv_dim = 256;
+  config.optimized_gating = true;
+  config.post_norm = PostNormType::Scale;
+  config.use_qk_norm = true;
+  return config;
+}
+
+static ModelConfig ConfigGemma3_270M() {
+  ModelConfig config = ConfigBaseGemmaV3();
+  config.display_name = "Gemma3_270M";
+  config.model = Model::GEMMA3_270M;
+  config.wrapping = PromptWrapping::GEMMA_IT;
+  config.model_dim = 640;
+  config.vocab_size = kGemmaV3VocabSize;  // new vocab size / tokenizer
+  config.max_seq_len = 32 * 1024;
+  LayerConfig layer_config = LayerConfigGemma3_270M_LM(config.model_dim);
+  config.num_layers = 18;
+  config.layer_configs = {config.num_layers, layer_config};
+  config.query_scale = QueryScaleType::SqrtKeySize;
+  // interleaved local / global attention
+  config.attention_window_sizes = RepeatedAttentionWindowSizes<18, 6>(
+      {512, 512, 512, 512, 512, config.max_seq_len});
+  return config;
+}
+
 static ModelConfig ConfigFromModel(Model model) {
   switch (model) {
     case Model::GEMMA2_2B:
@@ -499,6 +530,8 @@ static ModelConfig ConfigFromModel(Model model) {
       return ConfigGemma3_12B();
     case Model::GEMMA3_27B:
       return ConfigGemma3_27B();
+    case Model::GEMMA3_270M:
+      return ConfigGemma3_270M();
     default:
       HWY_ABORT("Model type %d unknown.", static_cast<int>(model));
   }
@@ -534,6 +567,8 @@ const char* ModelPrefix(Model model) {
       return "gemma3-12b";
     case Model::GEMMA3_27B:
       return "gemma3-27b";
+    case Model::GEMMA3_270M:
+      return "gemma3-270m";
     default:
       HWY_ABORT("Model type %d unknown.", static_cast<int>(model));
   }

gemma/configs.h

@@ -175,6 +175,7 @@ enum class Model {
   GEMMA3_1B,
   GEMMA3_12B,
   GEMMA3_27B,
+  GEMMA3_270M,
   kSentinel,
 };
 

python/configs.cc

@@ -91,6 +91,7 @@ PYBIND11_MODULE(configs, py_module) {
       .value("PALIGEMMA2_10B_224", Model::PALIGEMMA2_10B_224)
       .value("PALIGEMMA2_3B_448", Model::PALIGEMMA2_3B_448)
       .value("PALIGEMMA2_10B_448", Model::PALIGEMMA2_10B_448)
+      .value("GEMMA3_270M", Model::GEMMA3_270M)
   .value("PALIGEMMA_448", Model::PALIGEMMA_448);
 
   class_<TensorInfo>(py_module, "TensorInfo")