Raspberry Pi#
A new gadget, see http://www.raspberrypi.org
.
Installation , operation.#
Make sure you have a micro USB power supply that offers enough current (at least 700 mA) and good voltage. Use a voltmeter in case of doubt.
I had a 2 GB SD Card (the absolute minimum), and installed the default Raspbian “wheezy” on it, see http://www.raspberrypi.org/downloads.
After downloading and verifying the SHA1, you can unzip it and also check the partitions in it :
metskem@athena ~/Downloads $ ls -l 2012-12-16-wheezy-raspbian.img -rw-r--r-- 1 metskem metskem 1939865600 Jan 4 20:52 2012-12-16-wheezy-raspbian.img metskem@athena ~/Downloads $ file 2012-12-16-wheezy-raspbian.img metskem@athena ~/Downloads $ sudo dd if=2012-12-16-wheezy-raspbian.img of=/dev/sdb bs=4M 462+1 records in 462+1 records out 1939865600 bytes (1.9 GB) copied, 243.748 s, 8.0 MB/s metskem@athena ~/Downloads $
Stick the network cable in, and stick the power cable in.
You should see the red LED (PWR) see lighting up, and also after a few seconds all (4) other green and yellow LEDs.
If not, either your power supply is insufficient or your SD card is not properly formatted with the right 2 partitions (that was the case with me the first time).
After booting up the first challenge is to find out the IP address it got (DHCP), so I wrote a small shell script the iterates over all 25 addresses in the range and tries to ssh pi@${address} .
After first login (user pi password raspberry), you are advised to run the sudo raspi-config script. I did that to
- Expand root partition to fill SD card
- set the Timezone
- set the Locale
- run an update (apt-get)
Some "screenshots"#
metskem@athena ~/Downloads $ ssh pi@10.0.0.171 Linux raspberrypi 3.2.27+ #250 PREEMPT Thu Oct 18 19:03:02 BST 2012 armv6l The programs included with the Debian GNU/Linux system are free software; the exact distribution terms for each program are described in the individual files in /usr/share/doc/*/copyright. Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent permitted by applicable law. Last login: Sat Jan 5 14:59:34 2013 from 10.0.0.164
pi@raspberrypi ~ $ df -h Filesystem Size Used Avail Use% Mounted on rootfs 1.8G 1.5G 238M 86% / /dev/root 1.8G 1.5G 238M 86% / devtmpfs 220M 0 220M 0% /dev tmpfs 44M 200K 44M 1% /run tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 88M 0 88M 0% /run/shm /dev/mmcblk0p1 56M 17M 40M 30% /boot
pi@raspberrypi ~ $ sudo fdisk -l
Disk /dev/mmcblk0: 1967 MB, 1967128576 bytes
4 heads, 16 sectors/track, 60032 cylinders, total 3842048 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00017b69
Device Boot Start End Blocks Id System
/dev/mmcblk0p1 8192 122879 57344 c W95 FAT32 (LBA)
/dev/mmcblk0p2 122880 3842047 1859584 83 Linux
pi@raspberrypi ~ $ cat /proc/cpuinfo Processor : ARMv6-compatible processor rev 7 (v6l) BogoMIPS : 697.95 Features : swp half thumb fastmult vfp edsp java tls CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xb76 CPU revision : 7 Hardware : BCM2708 Revision : 000e Serial : 0000000095619558
pi@raspberrypi ~ $ uname -a Linux raspberrypi 3.2.27+ #250 PREEMPT Thu Oct 18 19:03:02 BST 2012 armv6l GNU/Linux pi@raspberrypi ~ $
Reboot after plugging in USB stick#
Because I only had a 2GB SD Card (I already ordered a 16GB class 10 card, next week in) and want to put more stuff on it, I inserted an extra USB stick in, this immediately made 4 of 5 LEDs go out. I suspect this required a short peak of current making the voltage reduce too much. It did automatically reboot and was back up in about 30 seconds.
Performance#
The performance of the thing is (as expected) not as we are used to with our Intel boxes. Also having a slow SD card makes the thing even slower. If you use top you see a lot of IOWAIT.
Installed stuff#
- locate
- vim
- default-jre-headless (and that just fitted on the SD card, only 88MB free)
JSPWiki#
The goal is to see how JSPWiki runs on it.
We need a container first, so unzipped the latest tomcat (7.0.34) to /mnt/sda1/apache-tomcat-7.0.34.
The created the webapps/wiki directory and unzipped the latest (2.9.1-svn-11) and tweaked jspwiki.properties (baseURL and pageDir and attachmentDIR).
Firing up the stuff, takes a loooong time, see attached jspwiki.log
, but it just works (as expected :-) )
Created an extra DNS alias for my domain and added some proxy statements to my main host, the wiki is now accessible at http://raspberrypi.computerhok.nl/wiki
Performance tomcat / JSPWiki#
See for details the logfile, but some performance related messages:
INFO: Server startup in 103644 ms 2013-01-05 16:48:29,964 [JSPWiki Lucene Indexer] INFO org.apache.wiki.search.LuceneSearchProvider - Full Lucene index finished in 10067 milliseconds.
You also notice the first time you get to the wiki and all JSP's have to be compiled, that takes several minutes !