From 98206a6a90912f79a487d53bf90bc6255713da5a Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Tue, 29 Aug 2023 16:03:45 +0200
Subject: [PATCH 1/2] main: fix performance issue with large dirs

cache the number of links for a directory instead of calculating it on
every stat.  It makes a huge difference when the directory has a lot
of entries.

Closes: https://github.com/containers/fuse-overlayfs/issues/401

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
---
 fuse-overlayfs.h |  2 ++
 main.c           | 13 +++++++++----
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/fuse-overlayfs.h b/fuse-overlayfs.h
index 49bace9..695446f 100644
--- a/fuse-overlayfs.h
+++ b/fuse-overlayfs.h
@@ -54,6 +54,8 @@ struct ovl_node
   struct ovl_node *next_link;
   unsigned int in_readdir;
 
+  size_t n_links;
+
   unsigned int do_unlink : 1;
   unsigned int do_rmdir : 1;
   unsigned int hidden : 1;
diff --git a/main.c b/main.c
index 2a8db29..a69ea48 100644
--- a/main.c
+++ b/main.c
@@ -941,9 +941,13 @@ rpl_stat (fuse_req_t req, struct ovl_node *node, int fd, const char *path, struc
   st->st_ino = node->tmp_ino;
   st->st_dev = node->tmp_dev;
 
-  if (node_dirp (node))
+  if (node->loaded && node->n_links > 0)
+    st->st_nlink = node->n_links;
+  else if (node_dirp (node))
     {
-      if (!data->static_nlink)
+      if (data->static_nlink)
+        st->st_nlink = 1;
+      else
         {
           struct ovl_node *it;
 
@@ -955,8 +959,8 @@ rpl_stat (fuse_req_t req, struct ovl_node *node, int fd, const char *path, struc
                 st->st_nlink++;
             }
         }
-      else
-        st->st_nlink = 1;
+
+      node->n_links = st->st_nlink;
     }
   else
     {
@@ -5157,6 +5161,7 @@ ovl_mkdir (fuse_req_t req, fuse_ino_t parent, const char *name, mode_t mode)
   e.attr_timeout = get_timeout (lo);
   e.entry_timeout = get_timeout (lo);
   node->ino->lookups++;
+  pnode->n_links++;
   fuse_reply_entry (req, &e);
 }
 

From 6931a9c088d0b110f41021e89073d6db83871a05 Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Tue, 29 Aug 2023 16:07:22 +0200
Subject: [PATCH 2/2] NEWS: tag 1.13

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
---
 NEWS | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/NEWS b/NEWS
index 26fcf48..575336c 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,7 @@
+* fuse-overlayfs-1.13
+
+- fix a performance issue when dealing with big directories.
+
 * fuse-overlayfs-1.12
 
 - change license to GPL-2.0-or-later.