Am 15.01.2008 um 17:32 schrieb Alexander Graf:
Jamie Lokier wrote:
Alexander Graf wrote:
I believe the 5% performance hit
that goes with them is no real problem, as most people should be
using
x86_64 nowadays anyway.
*Boggle*! x86_64 is only a few years old, and cheap low-power x86_64
laptops are relatively recent.
-- Jamie
So you really want to do dynamic retranslation on ancient hardware? To
me emulated systems already feel slow on really recent machines, I
don't want to go back to something even slower.
If you use kqemu there even is near no performance hit at all, which I
believe is the main use of qemu on i386 anyway. Furthermore x86_64 is
_way_ faster, as it provides a lot more registers.
I think the benefit you get from cutting the gcc3 dependency is way
more
important than a major performance hit that people will usually only
see
on the next release of qemu, by which time things have shifted towards
x86_64 even more.
One thing you don't seem to understand is that QEMU releases don't
upgrade our hardware, especially not from Apple. An x86_64 Mac Pro is
more than double the price for my PowerMac G5 back then. Don't think
about what people "should" be using in your opinion, look at what they
are actually using.
People want to run software, including Q or QEMU, on their hard- and
software, which may include ppc hardware as well as Panther/Tiger
operating systems ... both much more "ancient" than Intel Core 2 Duo
based Macs. And yes, it's "slow". Does that stop me? No. And you
likely don't have a kqemu on your Mac either. Occasionally trying an
image does not justify buying VMware Fusion, and such commercial
products only do virtualization anyway and are incapable of emulating
different hardware. Just in case you forgot, Open Source software in
general usually has the benefit of not being tied to the support
lifetimes of commercial vendors, forcing users to upgrade their (e.g.
Windows) OS - but pushing us to upgrade our hardware as soon as
something faster is out would be doing exactly that hardware-wise,
without substantial reason.
As a user, I don't want to do dynamic retranslation. I still don't
really understand how it works (seems more complicated than the JIT
I'm working with). I just want to emulate a machine in my preferred
environment, especially ppc64 and sparc64 targets for work on Open
Source software. QEMU is the only emulator I know that is on its way
there.
Flame me if you need to, but please stop this "everyone is using
x86_64 anyway" argument; if you have improvements specific to that
host, simply make them conditional, that's what configure is for.
With the gcc3 part I do agree.
Regards,
Andreas
