RE: [Qemu-devel] PPC emulation performance issues

[Bruce Beare (bbeare)]

Thank you.

I've determined that SVN delta number 3935 caused a 3
micro second performance hit for system calls on the
PREP image (not -m603). The hit doesn't appear to have been
due to the elimination of the push/pop and replacement of
them with the move - I don't know if it is cache/alignment with
the tlb data structure or the macro change... I'll look into that later.

This isn't, however, the main problem. SVN delta 4600 (changing the
variable dynamic translation buffer size) appears to have cause a
heavy hit on the application performance. I've just begun to look into
this
to see what's causing the problem.

-Bruce

-----Original Message-----
From: Aurelien Jarno [mailto:address@hidden 
Sent: Friday, February 13, 2009 1:00 PM
To: address@hidden
Subject: Re: [Qemu-devel] PPC emulation performance issues

On Wed, Feb 11, 2009 at 01:44:54PM -0800, Bruce Beare (bbeare) wrote:
> I am looking into a performance problem for the PPC m603 processor 
> emulation. I've seen a steady decline in performance of basic micro 
> benchmarks such as memory bandwith (lmbench bw_mem test). Just now, I 
> am building various versions of qemu-system-ppc from the SVN repo to 
> determine which commits cause the big drops.
> 

You should precise which version you are speaking about. If you are
comparing version 0.9.1 with the SVN, this is due to the conversion to
TCG.

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
address@hidden                 http://www.aurel32.net