All of lore.kernel.org
 help / color / mirror / Atom feed
From: Khiem Nguyen <khiem.nguyen.xt@renesas.com>
To: linux-sh@vger.kernel.org
Subject: Re: [PATCH 0/5] arm: shmobile: Lager Add USB and SATA support
Date: Fri, 12 Sep 2014 00:39:59 +0000	[thread overview]
Message-ID: <541240DF.6020604@renesas.com> (raw)
In-Reply-To: <1387370660-20481-1-git-send-email-valentine.barshak@cogentembedded.com>

Hi Hiep-san,

Thanks for your update.

On 9/11/2014 8:26 PM, カオ　ミン　ヒェップ wrote:
> Hi Khiem-san
> 
>> It seems SATA performance (write speed) is degraded after CPUFreq is enabled
>> (even performance governor is selected).
>>
>> Base on your test result so far:
>> T1 Upstream-v3.16-rc5: 66 MB/s
>> T2 v3.17-rc2 (CPUFreq disabled): ~ 66 MB/s
>> T3 v3.17-rc2 (CPUFreq enable / on-demand governor): 42.61MB/s
>> T4 v3.17-rc2 (CPUFreq disabled / performance governor ): 58.3MB/s
>>
>> The diff between T2 and T4 is ~8 MB/s (or 8% of 66 MB/s).
>> I guess we should try to find the cause of this regression.
>> (I wonder similar phenomenon occurs in backport version ...)

[snip]

> Have some miss in my way of the report yesterday.
> As yesterday results, T2 v3.17-rc2 (CPUFreq disabled) should be (367MB/(5.3s+1.0s)) ->58.2MB/s

[snip]

> And I have just re-confirmed T1 (Upstream-v3.16-rc5),
> On upstream-v3.16-rc5 SATA's writing speed should be 55.6MB/s as below.
> There is no uniformity in the speed calculation of SATA in our test team.
> That 66MB/s only is result of copy to SATA-HDD without umount the device before finish.
> Sorry for the inconvenience.
[snip] 

It makes sense now.
SATA performance does not degrade after CPUFreq is enabled (select performance governor).
>> T1 Upstream-v3.16-rc5 (CPUFreq disabled by default): -> 55.6MB/s
>> T2 v3.17-rc2 (CPUFreq disabled)                    : -> 58.2MB/s
>> T3 v3.17-rc2 (CPUFreq enable / on-demand governor) : 42.61MB/s
>> T4 v3.17-rc2 (CPUFreq disabled / performance governor ): 58.3MB/s

And we should take note SATA performance
when CPUfreq/on-demand governor is selected.
(perhaps, CPUFreq parameters should be tuned)

Thanks for your testing, Hiep-san.

>>>
>>> Thank you!
>>> Cao Minh Hiep.


-- 
Best regards,
KHIEM Nguyen

      parent reply	other threads:[~2014-09-12  0:39 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-18 12:44 [PATCH 0/5] arm: shmobile: Lager Add USB and SATA support Valentine Barshak
2013-12-19 10:09 ` Magnus Damm
2013-12-19 13:02 ` Valentine
2013-12-19 17:56 ` Valentine
2013-12-20 14:07 ` Valentine
2014-09-10  1:21 ` Ryusuke Sakato
2014-09-10  5:18 ` カオ　ミン　ヒェップ
2014-09-10  7:15 ` Ryusuke Sakato
2014-09-10  9:16 ` カオ　ミン　ヒェップ
2014-09-10  9:32 ` Khiem Nguyen
2014-09-11  9:35 ` カオ　ミン　ヒェップ
2014-09-11 10:20 ` Khiem Nguyen
2014-09-11 11:26 ` カオ　ミン　ヒェップ
2014-09-12  0:39 ` Khiem Nguyen [this message]

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=541240DF.6020604@renesas.com \
    --to=khiem.nguyen.xt@renesas.com \
    --cc=linux-sh@vger.kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.