From: Daniel Bevenius Date: Thu, 4 Sep 2025 13:40:44 +0000 (+0200) Subject: llama : set n_outputs to 1 to avoid 0 outputs mean-pooling (#15791) X-Git-Tag: upstream/0.0.6527~145 X-Git-Url: https://git.djapps.eu/?a=commitdiff_plain;h=d1e2adba65208d6de3d7f6f23b00c562ff5bb777;p=pkg%2Fggml%2Fsources%2Fllama.cpp llama : set n_outputs to 1 to avoid 0 outputs mean-pooling (#15791) * llama : set n_outputs to 1 to avoid 0 outputs mean-pooling This commit modifies the llama_context constructor to set n_outputs to 1. The motivation for this is that when using pooling, and specifically mean pooling, for embeddings having n_outputs set to 0 can lead to the following error: ```console $ build/bin/llama-embedding -m models/nomic-embed-text-1.5-Q4_K_M.gguf \ --pooling mean -p "Hello, how are you?" ... llama_context: CPU output buffer size = 0.12 MiB /home/danbev/work/ai/llama.cpp/ggml/src/ggml.c:3023: GGML_ASSERT(ggml_can_mul_mat(a, b)) failed 0x0000743c96d107e3 in __GI___wait4 (pid=292978, stat_loc=0x0, options=0, usage=0x0) at ../sysdeps/unix/sysv/linux/wait4.c:30 warning: 30 ../sysdeps/unix/sysv/linux/wait4.c: No such file or directory 30 in ../sysdeps/unix/sysv/linux/wait4.c 196 waitpid(child_pid, NULL, 0); 230 ggml_print_backtrace(); 3023 GGML_ASSERT(ggml_can_mul_mat(a, b)); 1823 cur = ggml_mul_mat(ctx0, ggml_cont(ctx0, ggml_transpose(ctx0, inp)), inp_mean); 18983 llm->build_pooling(cls, cls_b, cls_out, cls_out_b); 1399 auto * gf = model.build_graph(gparams); 292 auto * gf = graph_reserve(1, n_seqs, n_outputs, mctx.get(), true); 2329 auto * ctx = new llama_context(*model, params); 913 llama_context * lctx = llama_init_from_model(model, cparams); 105 common_init_result llama_init = common_init_from_params(params); [Inferior 1 (process 292976) detached] Aborted (core dumped) ``` Co-authored-by: Georgi Gerganov * add comment about not reserving graphs with zero outputs * add assert in graph_reserve to ensure n_outputs >= 1 --------- Co-authored-by: Georgi Gerganov --- diff --git a/src/llama-context.cpp b/src/llama-context.cpp index 2de6fcf0..6b3188be 100644 --- a/src/llama-context.cpp +++ b/src/llama-context.cpp @@ -285,6 +285,9 @@ llama_context::llama_context( const uint32_t n_seqs = cparams.kv_unified ? 1 : cparams.n_seq_max; const uint32_t n_tokens = std::min(cparams.n_ctx, cparams.n_ubatch); + // avoid reserving graphs with zero outputs + n_outputs = 1; + LLAMA_LOG_DEBUG("%s: worst-case: n_tokens = %d, n_seqs = %d, n_outputs = %d\n", __func__, n_tokens, n_seqs, n_outputs); // resolve automatic Flash Attention use @@ -1368,6 +1371,7 @@ llm_graph_result * llama_context::get_gf_res_reserve() const { ggml_cgraph * llama_context::graph_reserve(uint32_t n_tokens, uint32_t n_seqs, uint32_t n_outputs, const llama_memory_context_i * mctx, bool split_only) { LLAMA_LOG_DEBUG("%s: reserving a graph for ubatch with n_tokens = %4u, n_seqs = %2u, n_outputs = %4u\n", __func__, n_tokens, n_seqs, n_outputs); + GGML_ASSERT(n_outputs >= 1); if (n_tokens % n_seqs != 0) { n_tokens = ((n_tokens + (n_seqs - 1)) / n_seqs) * n_seqs; // round to next multiple of n_seqs