From: Aaron Lu <aaron.lu@intel.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: Alan Stern <stern@rowland.harvard.edu>,
"Rafael J. Wysocki" <rjw@sisk.pl>,
James Bottomley <James.Bottomley@hansenpartnership.com>,
Tejun Heo <tj@kernel.org>,
linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org,
Aaron Lu <aaron.lwe@gmail.com>, Shane Huang <shane.huang@amd.com>,
Oliver Neukum <oneukum@suse.de>
Subject: Re: [PATCH RESEND v11 0/4] block layer runtime pm
Date: Sat, 23 Mar 2013 11:37:13 +0800 [thread overview]
Message-ID: <514D2369.2010200@intel.com> (raw)
In-Reply-To: <20130322150958.GK25978@kernel.dk>
On 03/22/2013 11:09 PM, Jens Axboe wrote:
> On Fri, Mar 15 2013, Aaron Lu wrote:
>> In August 2010, Jens and Alan discussed about "Runtime PM and the block
>> layer". http://marc.info/?t=128259108400001&r=1&w=2
>> And then Alan has given a detailed implementation guide:
>> http://marc.info/?l=linux-scsi&m=133727953625963&w=2
>>
>> To test:
>> # ls -l /sys/block/sda
>> /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/block/sda
>>
>> # echo 10000 > /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/power/autosuspend_delay_ms
>> # echo auto > /sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/power/control
>> Then you'll see sda is suspended after 10secs idle.
>>
>> [ 1767.680192] sd 2:0:0:0: [sda] Synchronizing SCSI cache
>> [ 1767.680317] sd 2:0:0:0: [sda] Stopping disk
>>
>> And if you do some IO, it will resume immediately.
>> [ 1791.052438] sd 2:0:0:0: [sda] Starting disk
>>
>> For test, I often set the autosuspend time to 1 second. If you are using
>> a GUI, the 10 seconds delay may be too long that the disk can not enter
>> runtime suspended state.
>>
>> Note that sd's runtime suspend callback will dump some kernel messages
>> and the syslog daemon will write kernel message to /var/log/messages,
>> making the disk instantly resume after suspended. So for test, the
>> syslog daemon should better be temporarily stopped.
>>
>> A git repo for it, on top of v3.9-rc1:
>> https://github.com/aaronlu/linux.git blockpm
>
> I think it's about time we get this in, but the patchset isn't very
> friendly from a scsi vs block perspective. Can you re-shuffle the REQ_PM
> change, just do a separate patch for that. I'll get it queued up for
> 3.10 then.
Thanks Jens.
I'll spilt the first patch into two patches: one to introduce the REQ_PM
flag in block layer and one to use that flag in SCSI layer. Will send
out v12 soon.
Best regards,
Aaron
prev parent reply other threads:[~2013-03-23 3:37 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-15 9:05 [PATCH RESEND v11 0/4] block layer runtime pm Aaron Lu
2013-03-15 9:05 ` [PATCH RESEND v11 1/4] block: add a flag to identify PM request Aaron Lu
2013-03-15 9:05 ` [PATCH RESEND v11 2/4] block: add runtime pm helpers Aaron Lu
2013-03-15 9:05 ` [PATCH RESEND v11 3/4] block: implement runtime pm strategy Aaron Lu
2013-03-15 9:05 ` [PATCH RESEND v11 4/4] sd: change to auto suspend mode Aaron Lu
2013-03-22 15:09 ` [PATCH RESEND v11 0/4] block layer runtime pm Jens Axboe
2013-03-23 3:37 ` Aaron Lu [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=514D2369.2010200@intel.com \
--to=aaron.lu@intel.com \
--cc=James.Bottomley@hansenpartnership.com \
--cc=aaron.lwe@gmail.com \
--cc=axboe@kernel.dk \
--cc=linux-ide@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=oneukum@suse.de \
--cc=rjw@sisk.pl \
--cc=shane.huang@amd.com \
--cc=stern@rowland.harvard.edu \
--cc=tj@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 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).