Re: Flash File System Concerns

[Mark Hatle <fray@mvista.com>]

Prakash kanthi wrote:
> Folks,
>
> I have one concern regarding FFS. If you use flash for
> your entire filesystem including /var/log, /proc,
> etc.., you will be accessing flash too many times.
>
> And there is good chance that, your flash on the board
> reaches maximum number of accesses/writes limited by
> flash technology.
>
> How do people generally handle that in the industry.
> Especially, if you have on-board (non-replaceable)
> flash?

/proc is mounted from teh system and does not use flash.

Under the rules of the FHS, /var and /tmp should be mounted as a Read-Write
filesystem, the rest of the system (depending on options and distribution) can
be mounted Read-Only.

Now then, if you need things preserved between system reboots then you need to
have /var mounted on a "perminant" storage system.  /tmp can be mounted w/ the
"tmpfs" filesystem.  (Basically a ramdisk.)

The way that I generally recommend this stuff to customers is to symbolically
link /tmp to /var/tmp, mount /var as a tmpfs filesystem and then create the log,
spool, lock, etc directories as required for the system during the initscripts.

--Mark


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