ggml : add NUMA support (#1556)

* detect NUMA systems and pin work threads to nodes (linux)

* disable mmap prefetch/readahead for NUMA systems

* avoid sending finalize op to thread pool if it does nothing

* silence robot

* fix args

* make --numa a param

* recommendation that n_nodes evenly divide n_threads did not warrant such aggressive enforcement

* lower synchronization overhead

* statically allocate

* move numa state to g_state

* add description for --numa

* ggml : minor style changes

* ggml : minor style + try fix sanitizer build

* llama : allow to initialize backend with NUMA support

* llama : avoid ggml include in llama-util.h

* ggml : style / formatting

* ggml : fix handling of ops with n_threads > n_tasks > 1

* server : utilize numa parameter

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

llama.h

@@ -140,8 +140,9 @@ extern "C" {
 
     // TODO: not great API - very likely to change
     // Initialize the llama + ggml backend
+    // If numa is true, use NUMA optimizations
     // Call once at the start of the program
-    LLAMA_API void llama_init_backend();
+    LLAMA_API void llama_init_backend(bool numa);
 
     LLAMA_API int64_t llama_time_us();