CF cards wear out?

[Matthew West]

On Fri, Dec 12, 2003 at 08:49:05AM -0500, Francisco Reyes wrote:
> Do CF cards "wear out"? Aren't they like memory?

They are solid-state storage devices; a bit like RAM, except they
remember what's stored on them even when they're not connected to a
power source.  :-)

The pros of using CF is that its small, requires only a small amount
of power to run and has no moving parts (no noise).

The cons of using CF is that its storage capacity is lower than your
conventional HDDs, and it has a relatively much lower number of writes
in its lifespan (around 1,000,000 writes I think, it varies from
product to product).  The number of reads is obviously much higher
than that though.

However, if you're going to be using it to run a router or whatever,
you're probably only going to write to the thing once or twice to set
it up, and then set it to mount read-only and leave it there.

What you _don't_ want it doing is churning logfiles every day.  The
m0n0BSD image mounts /var as a memory file system, so you still get
your logfiles to watch, but they don't actually get written to the CF
card.  Of course, you will lose the files when the power is removed...

If you're going to be using a system like the Soekris boards and your
project requires a media that you can do a lot of writes too, I would
recommend something like IBM's Microdrives.  You should be able to fit
these inside the Soekris chassis without a problem.  The NET4801 has a
Microdrive IDE connector on the board.

-- 
mwest at uct.ac.za