X-MimeOLE: Produced By Microsoft Exchange V6.5
Received: by onstor-exch02.onstor.net 
	id <01C7FF01.D293DFCA@onstor-exch02.onstor.net>; Mon, 24 Sep 2007 15:22:49 -0800
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
Content-class: urn:content-classes:message
Subject: RE: Wireshark Red Hat 3 and 5 NFS sequential performance
Date: Mon, 24 Sep 2007 15:22:49 -0800
Message-ID: <BB375AF679D4A34E9CA8DFA650E2B04E05B463DD@onstor-exch02.onstor.net>
In-Reply-To: <20070924161627.066895ed@ripper.onstor.net>
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
Thread-Topic: Wireshark Red Hat 3 and 5 NFS sequential performance
Thread-Index: Acf/AO+ZNrwU7GGgRlKLOGbWNrovEAAAG/7w
References: <BB375AF679D4A34E9CA8DFA650E2B04E05A25C3D@onstor-exch02.onstor.net><BB375AF679D4A34E9CA8DFA650E2B04E05B46316@onstor-exch02.onstor.net> <20070924161627.066895ed@ripper.onstor.net>
From: "Maxim Kozlovsky" <maxim.kozlovsky@onstor.com>
To: "Andy Sharp" <andy.sharp@onstor.com>
Cc: "Fay Chong" <fay.chong@onstor.com>,
	"Paul Hammer" <paul.hammer@onstor.com>,
	"Jonathan Goldick" <jonathan.goldick@onstor.com>,
	"Jobi Ariyamannil" <jobi.ariyamannil@onstor.com>,
	"Brian Montero" <brian.montero@onstor.com>

Sure, but we are not there yet. For now, we have a problem with even
running unidirectional write, so trying bidirectional test will not give
a lot of new information.

>-----Original Message-----
>From: Andy Sharp
>Sent: Monday, September 24, 2007 4:16 PM
>To: Maxim Kozlovsky
>Cc: Fay Chong; Paul Hammer; Jonathan Goldick; Jobi Ariyamannil; Brian
>Montero
>Subject: Re: Wireshark Red Hat 3 and 5 NFS sequential performance
>
>The test that should demonstrate the problem is not two unidirectional
>tests running at the same time, but a bidirectional test:
>
>
>$ time dd if=3Dchewbaca of=3Dapeman bs=3D32k
>9181+1 records in
>9181+1 records out
>300870117 bytes (301 MB) copied, 246.651 seconds, 1.2 MB/s
>
>real    4m6.655s
>user    0m0.000s
>sys     0m0.940s
>
>
>Cheers,
>
>a
>
>On Mon, 24 Sep 2007 14:40:01 -0700 "Maxim Kozlovsky"
><maxim.kozlovsky@onstor.com> wrote:
>
>> What exactly was this test doing? Is it single direction, or
>> bidirectional? The excel spreadsheet seems to imply that it is
>> bidirectional.
>>
>> I've tried bidirectional test and got completely different results
>> with almost identical performance:
>>
>> rhel3 - read 30MB/sec write 46MB/sec,
>> rhel5 - read 29.6MB/sec write 53.1MB/s
>>
>> The test that I was running:
>>
>> Rh3
>>
>> time dd if=3D/1/file1 of=3D/dev/zero bs=3D32k ; skill -INT dd &
>> 86187+0 records in
>> 86187+0 records out
>>
>> real    1m27.021s
>> user    0m0.090s
>> sys     0m11.740s
>>
>> time dd if=3D/dev/zero of=3D/1/file2 bs=3D32k count=3D131072 ; skill =
-INT dd
&
>> 131072+0 records in
>> 131072+0 records out
>>
>> real    1m28.539s
>> user    0m0.160s
>> sys     0m19.460s
>>
>> rh5:
>>
>> time dd if=3D/dev/zero of=3D/1/file2 bs=3D32k count=3D131072 ; skill =
-INT dd&
>> 131072+0 records in
>> 131072+0 records out
>> 4294967296 bytes (4.3 GB) copied, 80.8301 seconds, 53.1 MB/s
>>
>> real    1m20.834s
>> user    0m0.081s
>> sys     0m14.097s
>>
>> time dd if=3D/1/file1 of=3D/dev/zero bs=3D32k ; skill -INT dd &
>> 72297+0 records in
>> 72296+0 records out
>> 2368995328 bytes (2.4 GB) copied, 80.0069 seconds, 29.6 MB/s
>>
>>
>> real    1m20.023s
>> user    0m0.047s
>> sys     0m1.866s
>>
>> Couple of things:
>>
>> Do not post the results of running "vs stat agg" as actual
>> performance, who knows what this code is doing. For the case of dd
>> the performance can be measured directly as shown above.
>>
>> With this high volume of traffic the Wireshark is lossy, you can not
>> rely on it to tell anything about dropped packets. Look at the TCP
>> stats for the number of retransmitted packets on the client and on
>> the filer instead (which by the way was 0 in my test on both rhel5
>> and rhel3).
>>
>> In probably already doing this, but I thought I'll mention it just in
>> case - you should unmount and remount the volume on the client and
vol
>> offline /vol online the volume on the filer between the tests to make
>> sure consistent initial state is used.
>>
>> Could you please create a script(s) which can be used to run your
>> test(s) so we know we are on a same page?
>>
>> Max
>>
>> _____________________________________________
>> From: Fay Chong
>> Sent: Sunday, September 23, 2007 5:49 PM
>> To: Paul Hammer; Jonathan Goldick; Jobi Ariyamannil; Andy Sharp;
Maxim
>> Kozlovsky
>> Cc: Brian Montero; Fay Chong
>> Subject: Wireshark Red Hat 3 and 5 NFS sequential performance
>>
>> Hi,
>>
>> Attached are some results from the Wireshark trace experiments on NFS
>> sequential read and write with Red Hat Linux release 3 and 5. The
>> Wireshark summaries seemed to have a lot of dropped packets as well
as
>> TCP acked lost segment and TCP Previous segment lost messages. The
>> traces were saved so they can be reviewed by others. Also the vsvr
>> stat agg throughput results are included. Tests were run with and
>> without the wireshark. Let's talk about reviewing the data and
>> refining the experiment.
>>
>> Thanks
>>
>> Fay
>>
>>  << File: wiresharkexp1.xls >>
>>
>>
>> Fay Chong
>> Sr. Performance Engineer
>> ONStor, Inc.
>> fay.chong@onstor.com
>> 408.376.3130 (w)
>>
>>
