Bump Windows max open files from 512 to 2048 (#620)

* Bump windows max open files from 512 to 2048

https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/setmaxstdio?view=msvc-160

* Make _GGML_STDIO_TARGET dependent of GGML_MAX_CONTEXTS for Windows

1 files changed, 18 insertions, 0 deletions

diff --git a/src/llama.cpp b/src/llama.cpp
index 58812fc8..0d29f24a 100644
--- a/src/llama.cpp
+++ b/src/llama.cpp
@@ -4245,6 +4245,24 @@ struct llama_model_loader {
             trace = atoi(getenv("LLAMA_TRACE"));
         }
 
+        #ifdef _WIN32
+            // Only bump maxstdio if the user really wants large contexts:
+            #if defined(GGML_MAX_CONTEXTS) && (GGML_MAX_CONTEXTS > 512)
+                // Cap at MSVC's hard limit of 8192 - https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/setmaxstdio?view=msvc-160
+                #if (GGML_MAX_CONTEXTS > 8192)
+                    #define _GGML_STDIO_TARGET 8192
+                #else
+                    #define _GGML_STDIO_TARGET GGML_MAX_CONTEXTS
+                #endif
+                int _setmaxstdio_ret = _setmaxstdio(_GGML_STDIO_TARGET);
+                if (_setmaxstdio_ret == -1) {
+                    LLAMA_LOG_INFO("%s: failed to set max stdio to %d. (setmaxstdio returned -1)\n", __func__, _GGML_STDIO_TARGET);
+                } else {
+                    LLAMA_LOG_INFO("%s: max stdio successfully set to %d\n", __func__, _setmaxstdio_ret);
+                }
+            #endif // GGML_MAX_CONTEXTS > 512
+        #endif // _WIN32
+
         if (param_overrides_p != nullptr) {
             for (const struct llama_model_kv_override * p = param_overrides_p; p->key[0] != 0; p++) {
                 kv_overrides.insert({std::string(p->key), *p});