User manual

3 Software Configuration
3.1.2. OMAP3 based Devices
The system images for OMAP3 based devices have two partitions:
1. FAT partition having files need to initialize and boot the system (MLO, u-boot.img, uEnv.txt
and uImage)
2. ext4 partition having Debian root file system
The OMAP CPU automatically loads x-loader (MLO) from the FAT partition and then the code
in x-loader takes over and loads U-Boot
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(u-boot.img), that takes care of Linux kernel (uImage).
Please refer to this wiki for detailed information about OMAP boot process Bootloader Project.
3.2. Swapping and Logging
Due to the fact that the flash memory has a finite number of erase-write cycles it is very important
to reduce them. Many applications use logging for information, recovery and debugging purposes,
this can lead to frequent flash usage. There are several possibilities to avoid this:
1. use external HDD attached via USB and redirect swapping and logging to it
2. disable swapping
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(remove swap entry in the /etc/fstab) and logging where it is possible
3. redirect the log stream via network
To redirect logged messages that need syslog edit /etc/syslog.conf and change all file destinations
to network destinations (see the example). Change
*.=info;*.=notice;*.=warn;\
auth,authpriv.none;\
cron,daemon.none;\
mail,news.none -/var/log/messages
to
*.=info;*.=notice;*.=warn;\
auth,authpriv.none;\
cron,daemon.none;\
mail,news.none @192.168.254.84
for further information refer to the syslog.conf manpage. To receive the log messages under
Linux you can use your existing syslog utility, for Windows you can use Kiwi Syslog Daemon
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or
any other Syslog daemon.
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http://www.denx.de/wiki/U-Boot
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To list swapping devices execute cat /proc/swaps
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www.kiwisyslog.com
May 2014 OnRISC User Manual 17