SERVER-68394 Ensure we do not yield strong locks upon startup recovery when _id index is missing

1 files changed, 4 insertions, 0 deletions

diff --git a/src/mongo/db/startup_recovery.cpp b/src/mongo/db/startup_recovery.cpp
index f9ab1c1052d..85510a5c8c0 100644
--- a/src/mongo/db/startup_recovery.cpp
+++ b/src/mongo/db/startup_recovery.cpp
@@ -156,6 +156,10 @@ bool checkIdIndexExists(OperationContext* opCtx, const CollectionPtr& coll) {
 Status buildMissingIdIndex(OperationContext* opCtx, Collection* collection) {
     LOGV2(4805002, "Building missing _id index", logAttrs(*collection));
     MultiIndexBlock indexer;
+    // This method is called in startup recovery so we can safely build the id index in foreground
+    // mode. This prevents us from yielding a MODE_X lock (which is disallowed).
+    indexer.setIndexBuildMethod(IndexBuildMethod::kForeground);
+
     ScopeGuard abortOnExit([&] {
         CollectionWriter collWriter(collection);
         indexer.abortIndexBuild(opCtx, collWriter, MultiIndexBlock::kNoopOnCleanUpFn);