Set remote cache version and backend type once in compilation metrics

Summary:
X-link: pytorch/pytorch#141707

This is causing FbFxGraphRemoteCache.init to no longer be idempotent, i.e. only safe to call once per compile. AOTAutogradCache initializes a new remote cache for the forward and the backward.
Technically, we could make AOTAutogradCache smart and globally thread through a single FbFxGraphRemoteCache everywhere. But there's no reason to do so, as this class is just the handle to access the cache. Plus, it's very brittle for FbFxGraphRemoteCache to not be safe to call multiple times.

(Same problem, different fix of D66502138)
ghstack-source-id: 256106154
exported-using-ghexport

Reviewed By: ezyang

Differential Revision: D66508492

fbshipit-source-id: 014722ba2cfbf9d30359e1eaa39062ad35cd907d

userbenchmark/dynamo/dynamobench/_dynamo/utils.py

@@ -996,6 +996,24 @@ def safe_str(item: Any) -> str:
         return ",".join(safe_str(item) for item in metric)
 
     structured_logging_overhead_s = torch._logging.get_structured_logging_overhead()
+
+    if torch._inductor.utils.should_use_remote_fx_graph_cache():
+        try:
+            from torch._inductor.fb.remote_cache import (
+                FbRemoteFxGraphCache,
+                REMOTE_CACHE_VERSION,
+            )
+        except ModuleNotFoundError:
+            REMOTE_CACHE_VERSION = None
+            inductor_fx_remote_cache_backend_type = None
+
+        remote_cache_version = REMOTE_CACHE_VERSION
+        backend = FbRemoteFxGraphCache.get_remote_backend()
+        inductor_fx_remote_cache_backend_type = type(backend).__name__
+    else:
+        inductor_fx_remote_cache_backend_type = None
+        remote_cache_version = None
+
     common_metrics = {
         "compile_id": str(torch._guards.CompileContext.current_compile_id()),
         "start_time_us": start_time_ns // 1000,
@@ -1013,6 +1031,8 @@ def safe_str(item: Any) -> str:
         "inductor_fx_remote_cache_miss_keys": _convert_collection_to_str(
             "inductor_fx_remote_cache_miss_keys"
         ),
+        "remote_cache_version": remote_cache_version,
+        "inductor_fx_remote_cache_backend_type": inductor_fx_remote_cache_backend_type,
     }
 
     # TODO: The following are legacy fields, populated from the fields that replace