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    * Don't create a swap partition on the CF card. Swapping is intensive reading/write process and it can wear out the CF card quite fast. For swapping, it's a good idea to use NFS, it might be even faster than CF.     * Don't create a swap partition on the CF card. Swapping is intensive reading/write process and it can wear out the CF card quite fast. For swapping, it's a good idea to use NFS.

This page is about running NetBSD on the Jornada 720.

TableOfContents

About

The Jornada 720 is a handheld PC manufactured by HP. It was first released in the fall of 1999 and production was discontinued at the end of 2001. It runs on Microsoft Windows CE 3.0 but it has been ported to NetBSD in 2001. At the end of summer 2005, I've bought a used Jornada 720 and since then became interested in improving (hardware) support for NetBSD. I've created this page to share my experience and knowledge with NetBSD on the Jornada 720 and to provide (hopefully useful) information.

Photos

First, some photos of the Jornada.

Kernel boot messages

[http://pointless.nl/~peter/jornada/dmesg.boot dmesg from a 4.99.49 kernel] (2008/01/13)

Tips

Here are a few tips I'd like to share, hopefully some might be useful for you.

Decrease writes to CF

CompactFlash (CF) cards have a limited lifetime. The individual cells on the card usually have a lifespan of a few thousand/million erase/write cycles. Secondly, writing is not very fast. So it's obvious that you want to put the amount of writes to CF to a minimum. Here are a few tips to do that.

  • Don't create a swap partition on the CF card. Swapping is intensive reading/write process and it can wear out the CF card quite fast. For swapping, it's a good idea to use NFS.
  • Mount the partitions on the CF card with -o noatime,nodevmtime. This will not update the access time on files and the modification time on device files so it might improve both read and write performance. Please note that some programs such as screenblank(1) will no longer function correctly.

  • Use tmpfs for /tmp and /var/run. When you do this, you'll need to add the following to /etc/rc.conf: critical_filesystems_local="${critical_filesystems_local} /var/run /tmp.

  • Don't log to files with syslogd. Comment out all entries in /etc/syslogd.conf and log to the tmpfs mount /tmp. You can also setup a tty for the log messages: *.* /dev/ttyE4.

Saving power

  • Keep brightness as low as possible (using wsconsctl(8)) and adjust contrast to improve readability.
  • Power off PCMCIA when you don't use the PCMCIA card. If the PCMCIA card is a network device, then you can simply do ifconfig nn down to remove the power sources.

Kernel tuning

Some kernel options can have a negative impact in performance. Therefore, I recommend to remove the following two options, which are only useful when you need to debug a problem.

options         DIAGNOSTIC      # internal consistency checks
options         DEBUG           # expensive debugging checks/support

The options IRQSTATS and KMEMSTATS manage statistics about interrupts and kernel memory. Unless you need these statistics, I recommend to remove the following options:

options         IRQSTATS        # manage IRQ statistics
options         KMEMSTATS       # kernel memory statistics

Configuration files

Here are some of the configuration files I'm using on the Jornada.

X configuration:

System files:

TODO

Some things that can be improved and/or I'm planning to work on (random order):

  • Add support for kloader(4).
  • Write an audio driver (needs 3 new drivers: SA-1110 DMA, SA-1111 SAC, UDA1344 codec and audio(9) interface).
  • Windows CE should do a "hard reset" when rebooting, that should fix the brightness problem.
  • Better suspend/resume support.

Jornada 720 (last edited 2009-08-25 17:25:05 by localhost)