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From: Ulrich Hecht <uli@suse.de>
Subject: Re: [Qemu-devel] [PATCH 2/9] S/390 CPU emulation
Date: Wed, 11 Nov 2009 12:46:25 +0200
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: Laurent Desnogues <laurent.desnogues@gmail.com>, qemu-devel@nongnu.org, agraf@suse.de

On Tuesday 10 November 2009, Aurelien Jarno wrote:
> I have tested it by removing all the block around tb_add_jump in
> cpu_exec.c. I have a speed loss of about 2.5x in the boot time of an
> x86_64 image.

I just tried it with qemu-system-x86_64, and with that I can observe a=20
noticable performance gain using TB chaining as well. Maybe it's simply=20
a lot more effective in system than in userspace emulation.

Anyway, having implemented it for BRC already, I might as well leave it=20
in for future generations to enjoy.

CU
Uli

--=20
SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG N=FCrnberg)