diff --git a/.gitignore b/.gitignore
--- a/.gitignore
+++ b/.gitignore
@@ -53,10 +53,11 @@
 # VS2017 and VSCode config files.
 .vscode
 .vs
-# clangd index
-.clangd
+# clangd index. (".clangd" is a config file now, thus trailing slash)
+.clangd/
+.cache
 # static analyzer regression testing project files
 /clang/utils/analyzer/projects/*/CachedSource
 /clang/utils/analyzer/projects/*/PatchedSource
 /clang/utils/analyzer/projects/*/ScanBuildResults
-/clang/utils/analyzer/projects/*/RefScanBuildResults
\ No newline at end of file
+/clang/utils/analyzer/projects/*/RefScanBuildResults
diff --git a/clang-tools-extra/clangd/index/Background.h b/clang-tools-extra/clangd/index/Background.h
--- a/clang-tools-extra/clangd/index/Background.h
+++ b/clang-tools-extra/clangd/index/Background.h
@@ -56,9 +56,9 @@
   using Factory = llvm::unique_function<BackgroundIndexStorage *(PathRef)>;
 
   // Creates an Index Storage that saves shards into disk. Index storage uses
-  // CDBDirectory + ".clangd/index/" as the folder to save shards. CDBDirectory
-  // is the first directory containing a CDB in parent directories of a file, or
-  // user's home directory if none was found, e.g. standard library headers.
+  // CDBDirectory + ".cache/clangd/index/" as the folder to save shards.
+  // CDBDirectory is the first directory containing a CDB in parent directories
+  // of a file, or user's home directory if none was found, e.g. stdlib headers.
   static Factory createDiskBackedStorageFactory(
       std::function<llvm::Optional<ProjectInfo>(PathRef)> GetProjectInfo);
 };
diff --git a/clang-tools-extra/clangd/index/BackgroundIndexStorage.cpp b/clang-tools-extra/clangd/index/BackgroundIndexStorage.cpp
--- a/clang-tools-extra/clangd/index/BackgroundIndexStorage.cpp
+++ b/clang-tools-extra/clangd/index/BackgroundIndexStorage.cpp
@@ -95,8 +95,8 @@
 };
 
 // Creates and owns IndexStorages for multiple CDBs.
-// When a CDB root is found, shards are stored in $ROOT/.clangd/index.
-// When no root is found, the fallback path is ~/.cache/clangd/index.
+// When a CDB root is found, shards are stored in $ROOT/.cache/clangd/index/.
+// When no root is found, the fallback path is ~/.cache/clangd/index/.
 class DiskBackedIndexStorageManager {
 public:
   DiskBackedIndexStorageManager(
@@ -115,7 +115,7 @@
     llvm::SmallString<128> StorageDir(FallbackDir);
     if (auto PI = GetProjectInfo(File)) {
       StorageDir = PI->SourceRoot;
-      llvm::sys::path::append(StorageDir, ".clangd", "index");
+      llvm::sys::path::append(StorageDir, ".cache", "clangd", "index");
     }
     auto &IndexStorage = IndexStorageMap[StorageDir];
     if (!IndexStorage)
diff --git a/clang-tools-extra/clangd/test/background-index.test b/clang-tools-extra/clangd/test/background-index.test
--- a/clang-tools-extra/clangd/test/background-index.test
+++ b/clang-tools-extra/clangd/test/background-index.test
@@ -15,8 +15,8 @@
 # RUN: clangd -background-index -lit-test < %t/definition.jsonrpc | FileCheck %t/definition.jsonrpc --check-prefixes=CHECK,BUILD
 
 # Test that the index is writing files in the expected location.
-# RUN: ls %t/.clangd/index/foo.cpp.*.idx
-# RUN: ls %t/sub_dir/.clangd/index/foo.h.*.idx
+# RUN: ls %t/.cache/clangd/index/foo.cpp.*.idx
+# RUN: ls %t/sub_dir/.cache/clangd/index/foo.h.*.idx
 
 # Test the index is read from disk: delete code and restart clangd.
 # RUN: rm %t/foo.cpp
diff --git a/llvm/.gitignore b/llvm/.gitignore
--- a/llvm/.gitignore
+++ b/llvm/.gitignore
@@ -59,8 +59,6 @@
 # VS2017 and VSCode config files.
 .vscode
 .vs
-# clangd index
-.clangd
 
 #==============================================================================#
 # Files created in tree by the Go bindings.