Revision as of 20:07, 21 October 2009

Description

A simple test to determine effect of SATA link power management settings on power consumption.
Privileges: Root
Runlevel: singleuser
ETA: 10 minutes

How to test

Live Image Friendly
You may run this test case using the USB or CD live image if you install the powertop utility with yum install powertop

Hotplug issues
SATA link power states other than max_performance may cause problems with hotplugable external SATA ports and devices attached to those ports may have problems. Internal devices should be unaffected.

System must remain idle
Please do not do any other work on the system while running this test, otherwise power usage figures may be inaccurate.

Make sure laptop battery is fully charged.
Reboot laptop to single user mode. Refer to the Install guide for more information about single user mode
Unplug AC power from the laptop.

Enable the max_performance link state using the following command:

for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo max_performance > $i; done

Obtain system power usage using the following command:
```
powertop -d -t 60 | grep 'Power usage'
```
Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the max_performance setting.

Enable the medium_power link state using the following command:

for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo medium_power > $i; done

Obtain system power usage using the following command:
```
powertop -d -t 60 | grep 'Power usage'
```
Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the medium_power setting.

Enable the min_power link state using the following command:

for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo min_power > $i; done

Obtain system power usage using the following command:
```
powertop -d -t 60 | grep 'Power usage'
```
Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the min_power setting.

Expected Results

Sample results

[root@laptop ~]# for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo medium_power > $i; done
[root@laptop ~]# powertop -d -t 60 | grep 'Power usage'
Power usage (ACPI estimate): 22.3W (1.9 hours)

Please add the following to the results table.

Power consumption for all three link power settings, max_performance, medium_power, min_power.
Your smolt system profile. (no need to resubmit if you have already for one of the other tests)
Please open bugs if you notice any abnormal behavior such as system hangs, kernel oops messages, serious IO performance degradation.
You may return your system to its default state by running the command in step 4 again or just reboot.

@@ Line 11: / Line 11: @@
 # Reboot laptop to single user mode.  Refer to the [http://docs.fedoraproject.org/install-guide/f{{FedoraVersion}}/en-US/html/s1-rescuemode-booting-single.html Install guide] for more information about single user mode
 # '''Unplug''' AC power from the laptop.
-# Enable max link performance using the following command:
+# Enable the '''max_performance''' link state using the following command:
 #: <pre>for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo max_performance > $i; done</pre>
-# Record power usage using the following command:
+# Obtain system power usage using the following command:
 #: <pre>powertop -d -t 60 | grep 'Power usage'</pre>
 # Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the '''max_performance''' setting.
-# <<FIXME>>
+# Enable the '''medium_power''' link state using the following command:
 #: <pre>for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo medium_power > $i; done</pre>
-# <<FIXME>>
+# Obtain system power usage using the following command:
 #: <pre>powertop -d -t 60 | grep 'Power usage'</pre>
 # Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the '''medium_power''' setting.
-# <<FIXME>>
+# Enable the '''min_power''' link state using the following command:
 #: <pre>for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo min_power > $i; done</pre>
-# <<FIXME>>
+# Obtain system power usage using the following command:
 #: <pre>powertop -d -t 60 | grep 'Power usage'</pre>
 # Record the ACPI power usage estimate printed in Watts(W). This will be the power consumption at the '''min_power''' setting.
 |results=
+{{admon/tip|Sample results|<pre>
+[root@laptop ~]# for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo medium_power > $i; done
+[root@laptop ~]# powertop -d -t 60 | grep 'Power usage'
+Power usage (ACPI estimate): 22.3W (1.9 hours)
+</pre>}}
 Please add the following to the results table.
 # Power consumption for all three link power settings, max_performance, medium_power, min_power.

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QA:Testcase Power Management alpm: Difference between revisions

Revision as of 20:07, 21 October 2009

Description

How to test

Expected Results