From: Tomasz Chmielewski <mangoo@wpkg.org>
To: Bart Van Assche <bart.vanassche@gmail.com>
Cc: Vladislav Bolkhovitin <vst@vlnb.net>,
linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org,
iscsitarget-devel@lists.sourceforge.net,
James Bottomley <James.Bottomley@hansenpartnership.com>,
scst-devel <scst-devel@lists.sourceforge.net>,
stgt@vger.kernel.org
Subject: Re: [Scst-devel] [ANNOUNCE]: Comparison of features sets between different SCSI targets (SCST, STGT, IET, LIO)
Date: Mon, 06 Apr 2009 21:05:24 +0200 [thread overview]
Message-ID: <49DA5274.5030708@wpkg.org> (raw)
In-Reply-To: <e2e108260904061201y1e73d1chca088e6f20b1ddf6@mail.gmail.com>
Bart Van Assche schrieb:
> On Mon, Apr 6, 2009 at 12:29 PM, Tomasz Chmielewski <mangoo@wpkg.org> wrote:
>> The target is running Debian Lenny 64bit userspace on an Intel Celeron
>> 2.93GHz CPU, 2 GB RAM.
>>
>> Initiator is running Debian Etch 64 bit userspace, open-iscsi 2.0-869, Intel
>> Xeon 3050/2.13GHz, 8 GB RAM.
>>
>>
>> Each test was repeated 6 times, "sync" was made and caches were dropped on
>> both sides before each test was started.
>>
>> dd parameters were like below, so 6.6 GB of data was read each time:
>>
>> dd if=/dev/sdag of=/dev/null bs=64k count=100000
>>
>>
>> Data was read from two block devices:
>> - /dev/md0, which is RAID-1 on two ST31500341AS 1.5 TB drives
>> - encrypted dm-crypt device which is on top of /dev/md0
>>
>> Encrypted device was created with the following additional options passed to
>> cryptsetup
>> (it provides the most performance on systems where CPU is a bottleneck, but
>> with decreased
>> security when compared to default options):
>>
>> -c aes-ecb-plain -s 128
>>
>>
>> Generally, CPU on the target was a bottleneck, so I also tested the load on
>> target.
>>
>>
>> md0, crypt columns - averages from dd
>> us, sy, id, wa - averages from vmstat
>>
>>
>> 1. Disk speeds on the target
>>
>> Raw performance: 102.17 MB/s
>> Raw performance (encrypted): 50.21 MB/s
>>
>>
>> 2. Read-ahead on the initiator: 256 (default); md0, crypt - MB/s
>>
>> md0 us sy id wa | crypt us sy id wa
>> STGT 50.63 4% 45% 18% 33% | 32.52 3% 62% 16% 19%
>> SCST (debug + no patches) 43.75 0% 26% 30% 44% | 42.05 0% 84% 1% 15%
>> SCST (fullperf + patches) 45.18 0% 25% 33% 42% | 44.12 0% 81% 2% 17%
>
> Hello Tomasz,
>
> How is it possible that for this test the read performance through
> STGT (50.63 MB/s) was higher than the read performance on the target
> (50.21 MB/s) ? Are you sure that all read buffers were flushed before
> this test was started ?
You're looking at wrong columns:
md0 crypt
STGT 50.63 32.52
RAW 102.17 50.21
--
Tomasz Chmielewski
http://wpkg.org
next prev parent reply other threads:[~2009-04-06 19:05 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-04 18:56 [ANNOUNCE]: Comparison of features sets between different SCSI targets (SCST, STGT, IET, LIO) Vladislav Bolkhovitin
2009-04-04 19:12 ` [Scst-devel] " Tomasz Chmielewski
2009-04-04 19:21 ` Vladislav Bolkhovitin
2009-04-06 9:44 ` Tomasz Chmielewski
2009-04-05 11:29 ` Bart Van Assche
2009-04-06 10:29 ` Tomasz Chmielewski
2009-04-06 10:40 ` Tomasz Chmielewski
2009-04-06 16:55 ` Vladislav Bolkhovitin
2009-04-06 18:27 ` Tomasz Chmielewski
2009-04-07 20:27 ` Bart Van Assche
2009-04-09 18:45 ` Vladislav Bolkhovitin
2009-04-14 11:07 ` Tomasz Chmielewski
2009-04-14 18:10 ` Vladislav Bolkhovitin
2009-04-06 19:01 ` Bart Van Assche
2009-04-06 19:05 ` Tomasz Chmielewski [this message]
[not found] ` <c9a3e4540904052019o3c89128eq52d9046fef7e2725@mail.gmail.com>
2009-04-06 7:32 ` Vladislav Bolkhovitin
[not found] ` <c9a3e4540904060057w75b5525an9c63486ed00ca9a5@mail.gmail.com>
2009-04-06 12:21 ` Vladislav Bolkhovitin
[not found] ` <c9a3e4540904060319l3c885641k1217fba468f1fcf8@mail.gmail.com>
2009-04-06 17:57 ` Vladislav Bolkhovitin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=49DA5274.5030708@wpkg.org \
--to=mangoo@wpkg.org \
--cc=James.Bottomley@hansenpartnership.com \
--cc=bart.vanassche@gmail.com \
--cc=iscsitarget-devel@lists.sourceforge.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=scst-devel@lists.sourceforge.net \
--cc=stgt@vger.kernel.org \
--cc=vst@vlnb.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).