Re: [Qemu-devel] Debian 7.8.0 SPARC64 on qemu - anything i can do to speedup the emulation?

[Dennis Luehring <dl.soluz@gmx.net>]

i will try that - thx

Am 27.08.2015 um 17:29 schrieb Artyom Tarasenko:
> On Tue, Jul 28, 2015 at 9:52 AM, Dennis Luehring <dl.soluz@gmx.net> wrote:
> > (i've posted the question already on qemu-discuss@nongnu.org but was toled
> > to better use this mailing list)
> >
> > i've prepared an Debian 7.8.0 image for SPARC64/qemu emulation for C/C++
> > development before-real-hardware big-endian/unaligned tests
> >
> > i've benchmarked compiling of single pugixml.cpp
> > (https://github.com/zeux/pugixml/blob/master/src/pugixml.cpp)
> >
> > qemu-system-sparc64: >180sek
> > x64 native : ~ 2sek
> >
> > so my sparc64 emulation is around 90 times slower then native x64
> >
> > my system:
> >
> > using lastest qemu git 2.3.x, with virtio for harddisk/network and qcow2
> > image
> >
> > https://depositfiles.com/files/sj20aqwp0 (~280MB
> > press the "regular download" button, wait some seconds, solve the
> > chapca, "download file in regular mode by browser"
> >
> > there is pugi_sparc.txt in the 7z which describes how to start,use and
> > what is installed in the image
> >
> > qemu runs natively under a ubuntu 15.04 (x64), Core i7, 8GB system doing
> > nothing but qemu
> >
>
> Since the guest  g++ performance problems are caused by MMU emulation,
> I think the fastest solution at the moment would be using the user
> mode emulation instead of the full system emulation. You can try
> mounting your debian disk image with guestfish (or nbd) on your ubuntu
> host and chroot into it with statically built qemu-sparc32plus (for
> the released Debian/sparc) or statically built qemu-sparc64 (for the
> unreleased Debian/sparc64) as described in [1] and [2]. I haven't
> tried launching g++, but at least some /bin utilities used to work
> with qemu-sparc32plus, at least back in 2011 [2].
> NB: I think mixing sparc32plus and sparc64 binaries would not work,
> but it should not be a problem, since the userspace of the released
> Debian/sparc is pure sparc32plus and the userspace of the unreleased
> Debian/sparc64 is pure sparc64.
>
> Artyom
>
> 1. https://wiki.debian.org/QemuUserEmulation
> 2. http://tyom.blogspot.de/2011/07/user-mode-emulation-for-linuxsparc64.html
>
>