From 646c911f81cec0a199afd5e0e41db40b5fe0c6b3 Mon Sep 17 00:00:00 2001
From: Elliott Slaughter <slaughter@cs.stanford.edu>
Date: Fri, 7 Aug 2026 11:50:59 -0700
Subject: [PATCH] Query Realm machine to figure out if we have GPUs to run on.

---
 bin/run-model/src/run-model/main.cc | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/bin/run-model/src/run-model/main.cc b/bin/run-model/src/run-model/main.cc
index 79830cfb6f..898faf9e22 100644
--- a/bin/run-model/src/run-model/main.cc
+++ b/bin/run-model/src/run-model/main.cc
@@ -95,6 +95,13 @@ int main(int argc, char **argv) {
                                          /*workSpaceSize=*/1024 * 1024,
                                          /*allowTensorOpMathConversion=*/true);
 
+        bool has_gpus = []() {
+          FlexFlow::Realm::Machine::ProcessorQuery pq(
+              FlexFlow::Realm::Machine::get_machine());
+          pq.only_kind(FlexFlow::Realm::Processor::Kind::TOC_PROC);
+          return pq.count() > 0;
+        }();
+
         PCGInstance pcg_instance = create_pcg_instance(
             /*ctx=*/ctx,
             /*mpcg=*/mpcg,
@@ -102,7 +109,7 @@ int main(int argc, char **argv) {
             /*loss=*/std::nullopt,
             /*input_tensors=*/input_tensors,
             /*device_handle=*/device_handle,
-            /*device_type=*/DeviceType::GPU);
+            /*device_type=*/has_gpus ? DeviceType::GPU : DeviceType::CPU);
 
         // begin training loop
         int num_epochs = 5;