Making the OS more robust

[edekker]

Hi there,

I'm sure many users of plugcomputers are facing this problem.
When you turn-off the computer by simple unplug it. (there is no button on it)
and after a while just replug it, i often need to scan the SD Card and USB drive.
Then reboot again.. and voila all goes well.
I use a FS with journaling on so the chance of actually corrupting the FS is not very high.

But this is not the best way to do this.. there has to be a better way.
Like doing immediate writes without caching. Getting rid of processes that do a lot of unneeded writing.
Or cache more and do more burst writing on non-important data, such as logs. I don't mind they are like 30 minutes behind.

how can i know which processes write a lot?
How can i make sure that linux immediately writes the data i want it to write and cache that what is not so important?

I'm not expecting a complete guide here.. just a few pointers in which directions i need to look would be nice.

[Confusticated]

immediately writes the data i want it to write and cache that what is not so important

This isn't really feasible, the delayed writes are controlled by the kernel, either you do, or you don't.

These parameters can be manipulated by accessing
/proc/sys/vm/dirty_writeback???

There is a little info in
Documentation/sysctl/vm.txt
but I would suggest 'google is your fiend'

NOTE it is not a good idea to turn off delayed writes on flash media, if you do, you can expect to start counting its life in weeks.
You will also loose the performance advantage, and may need to monitor the system carefully for disk thrashing.

turn-off the computer by simple unplug it

I never do this, i log in remotely over shh and run 'poweroff' from the prompt before turning off the power.

[edekker]

Thanks..  i also heared of some embedded kernels which are basically stripped down to the bare essentials.
The program that is required to run does not do any writes to disk.
 

[Confusticated]

Use 'flashybrid' and mount the filesystem read-only