From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33304) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1amE9L-0007pA-UU for qemu-devel@nongnu.org; Sat, 02 Apr 2016 01:31:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1amE9G-0005Rm-Ux for qemu-devel@nongnu.org; Sat, 02 Apr 2016 01:31:07 -0400 Received: from mail-lf0-x241.google.com ([2a00:1450:4010:c07::241]:33829) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1amE9G-0005Rh-Ln for qemu-devel@nongnu.org; Sat, 02 Apr 2016 01:31:02 -0400 Received: by mail-lf0-x241.google.com with SMTP id f127so13212503lff.1 for ; Fri, 01 Apr 2016 22:31:02 -0700 (PDT) Sender: Paolo Bonzini References: <56FE3045.2030003@redhat.com> <20160401084456.GF32728@redhat.com> <1459502310.7011.37.camel@redhat.com> <20160401101733.GI32728@redhat.com> <1459508875.7011.62.camel@redhat.com> <20160401111139.GK32728@redhat.com> <1459510371.7011.63.camel@redhat.com> <20160401114947.GM32728@redhat.com> <20160401153540.GD25490@morn.lan> <20160401184131.GP32728@redhat.com> <20160401200546.GA19187@morn.lan> From: Paolo Bonzini Message-ID: <56FF590B.9080409@redhat.com> Date: Sat, 2 Apr 2016 07:30:51 +0200 MIME-Version: 1.0 In-Reply-To: <20160401200546.GA19187@morn.lan> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Why is SeaBIOS used with -kernel? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin O'Connor , "Richard W.M. Jones" Cc: marc.mari.barcelo@gmail.com, Stefan Hajnoczi , qemu-devel@nongnu.org, Gerd Hoffmann On 01/04/2016 22:05, Kevin O'Connor wrote: > > I looked closer at your setup and it appears the SeaBIOS virtio-scsi > driver is very slow because it does a full search of all 256 possible > scsi targets. This full scan takes a lot of time. I put together a > quick patch (see below) to stop the scan early. Gerd/Paulo, do you > know if what I've done is valid and/or if there is a better way we can > limit the virtio-scsi scan? No, it's not possible because target numbers are arbitrary. We can submit all 256 requests at the same time perhaps. Paolo