Set remote cache version and backend type once in compilation metrics

Summary:
X-link: pytorch/pytorch#141967

(Got reverted due to a silly bug, fixed now.)

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
ghstack-source-id: 256244970
exported-using-ghexport

Reviewed By: laithsakka

Differential Revision: D66701970

fbshipit-source-id: a856faa8232a083725fecb802f7b14c0ac2cf09a

Author: jamesjwu

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,
+            )
+
+            remote_cache_version = REMOTE_CACHE_VERSION
+            backend = FbRemoteFxGraphCache.get_remote_backend()
+            inductor_fx_remote_cache_backend_type = type(backend).__name__
+        except ModuleNotFoundError:
+            remote_cache_version = None
+            inductor_fx_remote_cache_backend_type = None
+    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