From a55abe44aa5a7e2b0f350ea897b1fd481eba6ffe Mon Sep 17 00:00:00 2001
From: Xuan Son Nguyen <son@huggingface.co>
Date: Wed, 12 Aug 2026 13:47:09 +0200
Subject: [PATCH] metrics_flush_idle

---
 tools/server/server-context.cpp | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/tools/server/server-context.cpp b/tools/server/server-context.cpp
index 6b0eade736..c3afe3d901 100644
--- a/tools/server/server-context.cpp
+++ b/tools/server/server-context.cpp
@@ -2703,6 +2703,9 @@ private:
 
             if (all_idle) {
                 SRV_TRC("%s", "all slots are idle\n");
+
+                metrics_flush_idle();
+
                 return; // skip further processing
 
             } else {
@@ -3922,6 +3925,16 @@ private:
         }
     }
 
+    // flush any queued prompt metrics if all slots are now idle
+    void metrics_flush_idle() {
+        if (metrics.n_prompt_queued == 0) {
+            return;
+        }
+
+        llama_synchronize(ctx_tgt);
+        metrics.flush_prompt();
+    }
+
     void metrics_on_prediction(const server_slot & slot) {
         const uint64_t t_us    = slot.stats.t_gen_us();
         const uint64_t n       = slot.stats.n_gen;