Mailing-List: contact derby-user-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Derby Discussion" <derby-user@db.apache.org>
Received-SPF: neutral (nike.apache.org: local policy)
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=kaibo.eu; s=google;
        h=mime-version:in-reply-to:references:date:message-id:subject:from:to
         :content-type:content-transfer-encoding;
        b=XmnbpeYho6z3kCAVhkvy08MZDXhmWKQVtBenF4Uoe2/FTFIjESOlv2Tkz8bZMpX94S
         dxAYvnBnFfj1uN9s04vVp6tRFdGaNI2/lN2mzejR/xe8TFn/r7RbZ/zX8hUDdw1hBKAg
         K6WdR0InAgKITRHnK63Q4PfuBOW7dhYzrDaa0=
MIME-Version: 1.0
In-Reply-To: <4DE88F7A.3080700@gmail.com>
References: <106E976287A4486D80B08DA74C01C816@yang254121bef4>
	<4DE88F7A.3080700@gmail.com>
Date: Fri, 3 Jun 2011 10:54:50 +0200
Message-ID: <BANLkTikfYOs_7zc_prGQAm0FLAu2Q2bJxw@mail.gmail.com>
Subject: Re: performance issue on 64 bit JVM
From: =?UTF-8?Q?Peter_Ondru=C5=A1ka?= <peter.ondruska+derby@kaibo.eu>
To: Derby Discussion <derby-user@db.apache.org>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

Unless you need to address heap over 32bit JVM limits use 32bit JVM.
Just my EUR .02 :-)

2011/6/3 Arnaud Masson <amasson@gmail.com>:
> 64-bit uses more memory,
> so if your Xmx is too small,
> the 64-bit version may have more GC overhead.
>
> You can increase Xmx
> or activate "compressed-pointers" to have a better memory usage.
>
> (Also the max heap size must fit in physical memory, otherwise the swap
> on disk could kill perfs.)
>
>
> Le 03/06/2011 04:09, QA Wang Yang a =E9crit :
>> Dear Derby
>>
>> Could you tell me how tuning the performance issue?
>>
>> This is running sample query to fetch data from Derby database
>>
>> On my dual-core XP x-32 laptop the Corporate Overview takes 406(ms).
>> But we saw on the dual quad core it took 22973 (ms).
>>
>> I don't know why the performance became bad on my powerful machine.
>>
>> This is my test detail
>>
>> Query:
>> select * from Customer;
>> select * from product;
>> select * from order;
>> select * from Customer1;
>>
>> Dual-core XP SP3 32 bit,JDK1.6.0_25 32 bit,
>> Dual quad core Windows 2008 64 bit, JDK1.6.0_25 64 bit,
>>
>>
>> *32 bit Dual core
>> Fetched record size: 1413
>> Fetch record time: 250 (ms)
>> Fetched record size 8
>> Fetch record time: 15 (ms)
>> Fetched record size: 6
>> Fetch record time: 0 (ms)
>> Fetched record size: 1413 records
>> Fetch record time: 141 (ms)
>> =3D=3D=3D=3Dtotal 406 ms
>>
>> **64 bit Dual quad core
>> Fetched record size: 1413
>> Fetch record time: 11483 (ms)
>> Fetched record size 8
>> Fetch record time: 3 (ms)
>> Fetched record size: 6
>> Fetch record time: 4 (ms)
>> Fetched record size: 1413
>> Fetch record time: 11484 (ms)
>> =3D=3D=3D=3Dtotal 22973 ms
>>
>> Thanks a lot
>>
>>
>>
>> Wangyang
>> QA Group
>> Jinfonet Software, Inc.
>>
>> www.jinfonet.com
>> 2nd floor on the east of BEC Theatre
>> 135 Xi Zhi Men Wai Street, Xicheng District Beijing, China 100044
>> yang.wang@support.jinfonet.com
>> 86-10-68316633
>>
>> JReport
>> Embedded Reporting for Java Applications
>>
>>
>>
>
>