cuda : fix tensor size calculation for non-split buffer (#5145)

updated the n_task calculation to use max number of
threads possible. This has improved the prompt eval
performance by around 5% for DOT kernels and by
around 10% for MMLA kernels on AWS Graviton3.

ggml-alloc.c

@@ -335,7 +335,9 @@ bool ggml_tallocr_is_measure(ggml_tallocr_t alloc) {
 }
 
 size_t ggml_tallocr_max_size(ggml_tallocr_t alloc) {
-    return alloc->max_size;
+    // FIXME: changes in the tensor sizes compared to the measure graph may cause allocations to fail
+    // to avoid this, we add a 10% margin to the buffer size
+    return alloc->max_size + alloc->max_size/10;
 }
 
 // graph allocator

ggml-backend.c

@@ -30,7 +30,9 @@ size_t ggml_backend_buft_get_alignment(ggml_backend_buffer_type_t buft) {
 GGML_CALL size_t ggml_backend_buft_get_alloc_size(ggml_backend_buffer_type_t buft, struct ggml_tensor * tensor) {
     // get_alloc_size is optional, defaults to ggml_nbytes
     if (buft->iface.get_alloc_size) {
-        return buft->iface.get_alloc_size(buft, tensor);
+        size_t size = buft->iface.get_alloc_size(buft, tensor);
+        assert(size >= ggml_nbytes(tensor));
+        return size;
     }
     return ggml_nbytes(tensor);
 }

ggml-cuda.cu

@@ -9790,8 +9790,8 @@ static void ggml_cuda_mul_mat_id(const ggml_tensor * src0, const ggml_tensor * s
     // TODO: mmq/mmv support
 #endif
 
-    const int64_t nb11 = src1->nb[1];
-    const int64_t nb1  =  dst->nb[1];
+    const size_t nb11 = src1->nb[1];
+    const size_t nb1  =  dst->nb[1];
 
     const struct ggml_tensor * ids = src0;
     const int32_t id = ((int32_t *) dst->op_params)[0];
@@ -10304,15 +10304,11 @@ GGML_CALL static void ggml_backend_cuda_buffer_init_tensor(ggml_backend_buffer_t
 
     if (ggml_is_quantized(tensor->type)) {
         // initialize padding to 0 to avoid possible NaN values
-        int64_t row_low = 0;
-        int64_t row_high = ggml_nrows(tensor);
-        int64_t nrows_split = row_high - row_low;
-
-        size_t original_size = ggml_nbytes_split(tensor, nrows_split);
+        size_t original_size = ggml_nbytes(tensor);
         size_t padded_size = ggml_backend_buft_get_alloc_size(buffer->buft, tensor);
 
         if (padded_size > original_size && tensor->view_src == nullptr) {
-            CUDA_CHECK(cudaMemsetAsync((char *)tensor->data + original_size, 0, padded_size - original_size, g_cudaStreams[ctx->device][0]));
+            CUDA_CHECK(cudaMemset((char *)tensor->data + original_size, 0, padded_size - original_size));
         }
     }
 }
@@ -10415,12 +10411,7 @@ GGML_CALL static size_t ggml_backend_cuda_buffer_type_get_alignment(ggml_backend
 }
 
 GGML_CALL static size_t ggml_backend_cuda_buffer_type_get_alloc_size(ggml_backend_buffer_type_t buft, const ggml_tensor * tensor) {
-    int64_t row_low = 0;
-    int64_t row_high = ggml_nrows(tensor);
-    int64_t nrows_split = row_high - row_low;
-
-    size_t size = ggml_nbytes_split(tensor, nrows_split);
-
+    size_t size = ggml_nbytes(tensor);
     int64_t ne0 = tensor->ne[0];
 
     if (ggml_is_quantized(tensor->type)) {

ggml.c

@@ -16597,7 +16597,7 @@ static int ggml_get_n_tasks(struct ggml_tensor * node, int n_threads) {
             } break;
         case GGML_OP_SOFT_MAX:
             {
-                n_tasks = MIN(MIN(4, n_threads), ggml_nrows(node->src[0]));
+                n_tasks = MIN(n_threads, ggml_nrows(node->src[0]));
             } break;
         case GGML_OP_CONV_TRANSPOSE_1D:
             {

scripts/run-with-preset.py

@@ -46,7 +46,7 @@ Formatting considerations:
 - To define multiple "reverse_prompt" properties simultaneously the expected format is a list of strings.
 - To define a tensor split, pass a list of floats.
 """
-usage = "run_with_preset.py [-h] [yaml_files ...] [--<ARG_NAME> <ARG_VALUE> ...]"
+usage = "run-with-preset.py [-h] [yaml_files ...] [--<ARG_NAME> <ARG_VALUE> ...]"
 epilog = ("  --<ARG_NAME> specify additional CLI ars to be passed to the binary (override all preset files). "
           "Unknown args will be ignored.")
 

tests/.gitignore

@@ -1,2 +1,3 @@
 *
 !*.*
+test-c.o