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Message-ID: <4bebff790808050011n7b7f5906x6bb563ec19770c11@mail.gmail.com>
Date: Tue, 5 Aug 2008 11:11:31 +0400
From: "Aleksey Shipilev" <aleksey.shipilev@gmail.com>
To: dev@harmony.apache.org
Subject: Re: patch for HARMONY-5901 is ready
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References: <255079590808042103r39efdb66g8f79eeb9d6045888@mail.gmail.com>

On Tue, Aug 5, 2008 at 8:03 AM, xiaoming gu <xiaoming.gu@gmail.com> wrote:
> Hi, guys. The patch for harmony-5901 is ready.
At last! Thanks, Xioaming!

> I compared the performance for all the 5 benchmarks in "Java vs. C
> benchmark" by Stefan Krause on my desktop
> workstation (Intel Core 2 Quad Q9550@2.83GHz, 3.23G RAM, Windows XP SP2).
> With MUL/DIV replaced by shift,
> spectralnorm is improved more than 29% (from 450258 msec to 319578 msec)
Can you spend some time and measure how much boost there is, in case
your _manual_ change of MUL/DIV operations to shifts? I had measured
+60% boost, so it would be great to conclude whether yours +30% is
connected with patch overheads (handling negative operands, I guess)
or your environment.

Thanks,
Aleksey.