From: Gerd Hoffmann <kraxel@redhat.com>
To: "Richard W.M. Jones" <rjones@redhat.com>
Cc: "Marc Marí" <markmb@redhat.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Why is SeaBIOS used with -kernel?
Date: Mon, 21 Mar 2016 08:58:27 +0100 [thread overview]
Message-ID: <1458547107.4299.7.camel@redhat.com> (raw)
In-Reply-To: <20160319203124.GB19398@redhat.com>
On Sa, 2016-03-19 at 20:31 +0000, Richard W.M. Jones wrote:
> I've been analyzing the libguestfs appliance[1] boot time. See
> attached file, especially the end of it.
>
> About 50% of the boot time is because of SeaBIOS.
And the bulk of that is loading the kernel from fw_cfg.
> I'm using the qemu -kernel option. I understand that the kernel needs
> some BIOS features, eg. video stuff, E820. But kvmtool comes with a
> really minimal BIOS that implements a tiny number of calls[2] and is
> far faster than SeaBIOS.
>
> Is there something I'm missing, or for Linux + -kernel could we use a
> much simpler BIOS?
marc (cc'ed) worked on porting the linuxboot option rom over to use the
new fwcfg dma interface, which should make things a order of magnitude
faster. That seems to be stalled though. Marc?
cheers,
Gerd
next prev parent reply other threads:[~2016-03-21 7:58 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-19 20:31 [Qemu-devel] Why is SeaBIOS used with -kernel? Richard W.M. Jones
2016-03-21 7:58 ` Gerd Hoffmann [this message]
2016-03-21 8:37 ` Richard W.M. Jones
2016-03-21 9:40 ` Gerd Hoffmann
2016-03-31 9:21 ` Stefan Hajnoczi
2016-03-31 16:22 ` Kevin O'Connor
[not found] ` <20160331221039.GA32728@redhat.com>
2016-03-31 22:17 ` Richard W.M. Jones
2016-03-31 22:44 ` Kevin O'Connor
2016-04-01 7:55 ` Richard W.M. Jones
2016-04-01 8:03 ` Paolo Bonzini
2016-04-01 8:47 ` Richard W.M. Jones
2016-04-01 8:51 ` Paolo Bonzini
2016-04-01 8:57 ` Richard W.M. Jones
2016-04-01 9:05 ` Paolo Bonzini
2016-04-01 8:02 ` Richard W.M. Jones
2016-04-01 8:11 ` Paolo Bonzini
2016-04-01 8:14 ` Richard W.M. Jones
2016-04-01 8:24 ` Paolo Bonzini
2016-04-01 8:44 ` Richard W.M. Jones
2016-04-01 8:47 ` Paolo Bonzini
2016-04-01 8:49 ` Vasiliy Tolstov
2016-04-01 9:16 ` Dr. David Alan Gilbert
2016-04-01 9:18 ` Gerd Hoffmann
2016-04-01 10:17 ` Richard W.M. Jones
2016-04-01 11:07 ` Gerd Hoffmann
2016-04-01 11:11 ` Richard W.M. Jones
2016-04-01 11:20 ` Richard W.M. Jones
2016-04-01 11:21 ` Paolo Bonzini
2016-04-01 11:26 ` Richard W.M. Jones
2016-04-05 4:38 ` Kevin Wolf
2016-04-05 8:04 ` Richard W.M. Jones
2016-04-05 8:11 ` Kevin Wolf
2016-04-05 9:19 ` Richard W.M. Jones
2016-04-05 9:26 ` Kevin Wolf
2016-04-01 11:32 ` Gerd Hoffmann
2016-04-01 11:49 ` Richard W.M. Jones
2016-04-01 15:35 ` Kevin O'Connor
2016-04-01 16:03 ` Paolo Bonzini
2016-04-01 18:41 ` Richard W.M. Jones
2016-04-01 18:59 ` Richard W.M. Jones
2016-04-01 19:04 ` Kevin O'Connor
2016-04-01 19:10 ` Richard W.M. Jones
2016-04-01 19:15 ` Richard W.M. Jones
2016-04-01 19:44 ` Kevin O'Connor
2016-04-01 20:25 ` Richard W.M. Jones
2016-04-01 20:05 ` Kevin O'Connor
2016-04-01 20:46 ` Richard W.M. Jones
2016-04-01 22:25 ` Kevin O'Connor
2016-04-02 7:51 ` Richard W.M. Jones
2016-04-02 5:30 ` Paolo Bonzini
2016-04-01 15:08 ` Kevin O'Connor
2016-04-01 14:58 ` Kevin O'Connor
2016-04-01 15:06 ` Richard W.M. Jones
2016-04-01 15:14 ` Kevin O'Connor
2016-04-01 8:19 ` Richard W.M. Jones
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