Re: kern/56329: nvme(4) takes long time to umount

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/56329; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/56329: nvme(4) takes long time to umount
Date: Fri, 6 Aug 2021 06:54:56 -0700 (PDT)

 On Fri, 6 Aug 2021, J. Hannken-Illjes wrote:
 
 > Given the null mounts it is possible you removed nodes
 > below the null mount and these nodes become open-but-removed
 > because the null layer keeps a (last) reference.
 >
 > Does the unmount speed up if you unmount the null mounts
 > first and sync?
 
 If I try to umount(8) the SSD while the null mounts are still in
 use, I would expect to see EBUSY when trying to umount(8) the SSD
 since the mount-point itself is still referenced.
 
 I hvae tried to umount(8) the null-fs first, and I have tried to
 sync(8) first, and I have tried doing both before attempting to
 umount(8) the SSD.  It does not matter, it still takes "a long
 time" for umount(8) to complete.
 
 
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