Power Log Collector
The Power Log Collectors boot an XO and copy the power logs to itself before shutting the laptop down.
Note: will not work on secured laptops without signing.
There are two versions provided here. One uses Tiny Core Linux, and the other uses Open Firmware.
|collector||supported hardware||minimum firmware||time taken|
|Tiny Core Linux based||XO-1 XO-1.5||none||a couple of minutes|
|Open Firmware based||XO-1 XO-1.5 XO-1.75||Q2F09 Q3C05 Q4D12||less than a minute|
Tiny Core Linux
How to Use
- Download Power-log-collector.tar.bz2 and unpack onto a USB flash drive,
- Shut down the XO,
- Insert the USB drive, and
- Turn on the XO.
The XO will collect the power logs, print a message saying has done so and then shut down.
Theory of Operation
- Based on Tiny Core Linux,
- An Open Firmware Boot Script selects the XO-1 or XO-1.5 kernel,
- The initial ramdisk mounts /dev/sda (which should be the first USB drive), and
- executes rc.local on that drive, which does the collection.
How it was Made
It was made by remastering Tiny Core Linux.
Unpack the initial ramdisk to the current directory:
# gunzip <../initrd.gz | cpio -i
Modify the files as needed, then repack the initial ramdisk:
# find | sudo cpio -o -H newc --quiet | gzip -2 > ../initrd.gz
Then assemble into a .tar.bz2 for download.
The script that does the collection:
#!/bin/sh uname -a | grep _xo1- if [ $? -eq 0 ] then echo detected xo-1.0 XO_ROOT=mtdblock0 XO_FS=jffs2 else echo detected xo-1.5 XO_ROOT=mmcblk0p2 XO_FS=ext3 fi mkdir -p /mnt/$XO_ROOT mount -t $XO_FS -o ro /dev/$XO_ROOT /mnt/$XO_ROOT mkdir -p /mnt/sda1/power-logs cp /mnt/$XO_ROOT/home/olpc/power-logs/* /mnt/sda1/power-logs umount /mnt/$XO_ROOT mount /dev/sda1 /mnt/sda1 -o remount,ro sync echo Power Logs Recovered echo Shutting down in 10 seconds echo You may remove the USB now sleep 10 poweroff
A bootable filesystem for USB drive which will save the power logs from a set of OLPC laptops for later analysis, for use on XO-1.75, XO-1.5, and XO-1.
Preparing the drive
Select a USB drive with at least 128MB capacity, and preferably nothing important on it.
- download save-power-logs-1.0.zip,
- unpack onto a USB drive.
This will create a boot directory containing the program.
This works with either the common FAT filesystem or ext2.
- for FAT filesystems, please use dosfsck, scandisk, Disk Utility or other tools to ensure the filesystem is without errors,
- for ext2 filesystems, please use Open Firmware Q4D12 or later.
Using the drive
- ensure the laptop is off,
- insert the drive,
- press the power button,
- wait for the green screen,
- remove the drive,
- move to the next laptop.
The data will be placed in a pwr.tar file on the USB drive.
Theory of operation
The first time it is booted, the program creates a pwr.tar file on the USB drive containing the power logs.
The second and subsequent boots append new entries to the pwr.tar file.
Running the collector twice on a laptop is harmless, in that the duplicate entries added to the file supersede the previous entries.