svn commit: r361399 - head/sys/fs/fuse

[Alan Somers]

Author: asomers
Date: Fri May 22 18:03:14 2020
New Revision: 361399
URL: https://svnweb.freebsd.org/changeset/base/361399

Log:
  Disable nullfs cacheing on top of fusefs
  
  Nullfs cacheing can keep a large number of vnodes active.  That results in
  more active FUSE file handles, causing some FUSE servers to use extra
  resources.  Disable nullfs cacheing for fusefs, just like we already do for
  NFSv4.
  
  PR:		245688
  Reported by:	MooseFS FreeBSD Team <freebsd at moosefs.pro>
  MFC after:	2 weeks

Modified:
  head/sys/fs/fuse/fuse_vfsops.c

Modified: head/sys/fs/fuse/fuse_vfsops.c
==============================================================================
--- head/sys/fs/fuse/fuse_vfsops.c	Fri May 22 17:52:09 2020	(r361398)
+++ head/sys/fs/fuse/fuse_vfsops.c	Fri May 22 18:03:14 2020	(r361399)
@@ -425,6 +425,11 @@ fuse_vfsop_mount(struct mount *mp)
 	 */
 	mp->mnt_flag &= ~MNT_LOCAL;
 	mp->mnt_kern_flag |= MNTK_USES_BCACHE;
+	/* 
+	 * Disable nullfs cacheing because it can consume too many resources in
+	 * the FUSE server.
+	 */
+	mp->mnt_kern_flag |= MNTK_NULL_NOCACHE;
 	MNT_IUNLOCK(mp);
 	/* We need this here as this slot is used by getnewvnode() */
 	mp->mnt_stat.f_iosize = maxbcachebuf;