Re: kern/38990: Unmounting a disk fails the first time

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/38990; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost, apb%cequrux.com@localhost
Subject: Re: kern/38990: Unmounting a disk fails the first time
Date: Sat, 21 Jun 2008 20:39:49 +0000

 On Fri, Jun 20, 2008 at 09:30:02AM +0000, Andrew Doran wrote:
  >>    $ sudo mount -t ffs /dev/sd0e /mnt
  >>    $ rsync /something/ /mnt/something/ # a large directory tree
  >>    $ sudo umount /mnt
  >>    umount: /mnt: Device busy
  >>    $ sync ; sleep 1 ; sync ; sleep 1 ; sync
  >>    $ sudo umount /mnt
  >>    [ no error ]
  >  
  >  It's due to the kernel's 'vrele' thread. Sometimes we have to defer
  >  VOP_INACTIVE because of the horrible locking requirements. It always
  >  gets done for layered file systems. The delay is about one second.
 
 Is it worth installing a workaround into umount(8)?
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost