From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
To: Paul Schlacter <wlfightup@gmail.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] qemu disk use writeback don't take effect in centos 7.2 1511
Date: Wed, 1 Nov 2017 09:45:38 +0000 [thread overview]
Message-ID: <20171101094537.GA2786@work-vm> (raw)
In-Reply-To: <CADak6y5eSo9=C2FJx+cTdqxArWeQqNDAvVgY+vS7H-9yGeuZvw@mail.gmail.com>
* Paul Schlacter (wlfightup@gmail.com) wrote:
> qemu version: 2.9.0
> image: centos 7.2 1511 raw
> cache mode: writeback
>
>
> In centos7.2 time, the use of writeback and none, the result of dd disk is
> the same io, no change
>
> But I replaced centos7.1 centos7.3 centos7.4 when writeback was
> significantly faster than none
>
> Would like to ask what is going on, how to solve ?
Hi Paul,
Can you just clarify your setup please; do you mean that
with the same qemu setup but a 7.2 guest rather than a 7.1/7.3 guest
the behaviour changes?
Dave
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
next prev parent reply other threads:[~2017-11-01 9:45 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-01 7:44 [Qemu-devel] qemu disk use writeback don't take effect in centos 7.2 1511 Paul Schlacter
2017-11-01 9:45 ` Dr. David Alan Gilbert [this message]
[not found] ` <CADak6y485_OSHrzji4Wq7_3vOrK+ch6Vm1FW1RMidSzoO3U-kQ@mail.gmail.com>
2017-11-01 12:03 ` Paul Schlacter
2017-11-03 3:46 ` Paul Schlacter
2017-11-03 9:10 ` Dr. David Alan Gilbert
2017-11-03 10:09 ` Stefan Hajnoczi
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