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: Wed, 20 Apr 2022 07:50:15 -0700 (PDT)

 On Wed, 20 Apr 2022, J. Hannken-Illjes wrote:
 
 > Finally got a laptop with
 >     nvme0: SAMSUNG MZVLB256HAHQ-000L7, firmware 0L2QEXD7, serial =
 > S41GNB0K593889
 > and see unmount times of 10 .. 12 seconds with a DIAGNOSTIC + DEBUG + =
 > LOCKDEBUG
 > kernel.  All this time is spent in the first vflush().
 >
 > On a GENERIC kernel without DIAGNOSTIC etc the unmount time goes down to =
 > less
 > than a second and the disk becomes much faster.
 >
 > What kind of kernel are/were you using?
 
 All of my kernels have DEBUG and DIAGNOSTIC enabled.  I do not have
 LOCKDEBUG.
 
 
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