llama_model_loader: support multiple split/shard GGUFs (#6187)

* split: support in llama_model_loader

* avoid copying the entire vector

Co-authored-by: slaren <slarengh@gmail.com>

* split: move llama_tensor_offset to llama_model_loader

* llama_model_loader: PR feedbacks:
 - use only one gguf_context for metadata only
 - store all ggml_context in a vector as the files and mappings
 - store all weights in a vector along with the source tensor
 - rename ctx_gguf to meta
 - rename ctx_meta to contexts

* avoid copying the entire vector

* Simplify this by making these optional, switch some layer creation tensor optional

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

* Handle optional tensors

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

* llama_model_loader: fail if backend cannot allocate buffer

* fix mmap buffer management

* llama_model_loader: map file to backend buffer if the allocation succeeds only

* llama_model_loader: only map tensors included in the context

* llama_model_loader: minor, use same variable name for consistency, fix spacing in types cast

* llama_model_loader: fail if any of backend buffer cannot be allocated

* spacing

Co-authored-by: slaren <slarengh@gmail.com>

* fix loop over pointer

Co-authored-by: slaren <slarengh@gmail.com>

* llama_model_loader: if n_tensors declared not equals to loaded tensors in split, throw an exception instead of asserting

* llama_model_loader: ensure mappings vector has the expected size

* llama_model_loader:  use at instead of operator[] if this should never add to the map.

* llama_model_loader: immediately add the backend buffer to the model buffers in order to free them if an error occurs in the next allocation. Reserve the expected size.

* llama_model_loader: be sure the model mappings has enough capacity before allocating backend buffer

* llama_model_loader: fix map -> unordered map

* llama_split_prefix: use a clearer version, not pass split path len but dest max len.

Co-authored-by: Xuan Son Nguyen <thichthat@gmail.com>

* llama : minor

ggml-ci

* llama : introduce some typedef helpers

* docs: add model shard in hot topic

* llama_model_loader: put mapping in a unique_ptr from the moment it is allocated

Co-authored-by: slaren <slarengh@gmail.com>

* fix llama_split_prefix

---------

Co-authored-by: slaren <slarengh@gmail.com>
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
Co-authored-by: Xuan Son Nguyen <thichthat@gmail.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/llama.h b/llama.h
index 40dcf54e..7e8ac4b6 100644
--- a/llama.h
+++ b/llama.h
@@ -960,6 +960,16 @@ extern "C" {
                                 int32_t   n_past,
                                 int32_t   n_predict);
 
+    /// @details Build a split GGUF final path for this chunk.
+    ///          llama_split_path(split_path, sizeof(split_path), "/models/ggml-model-q4_0", 2, 4) => split_path = "/models/ggml-model-q4_0-00002-of-00004.gguf"
+    //  Returns the split_path length.
+    LLAMA_API int llama_split_path(char * split_path, size_t maxlen, const char * path_prefix, int split_no, int split_count);
+
+    /// @details Extract the path prefix from the split_path if and only if the split_no and split_count match.
+    ///          llama_split_prefix(split_prefix, 64, "/models/ggml-model-q4_0-00002-of-00004.gguf", 2, 4) => split_prefix = "/models/ggml-model-q4_0"
+    //  Returns the split_prefix length.
+    LLAMA_API int llama_split_prefix(char * split_prefix, size_t maxlen, const char * split_path, int split_no, int split_count);
+
     // Performance information
     LLAMA_API struct llama_timings llama_get_timings(struct llama_context * ctx);