[geeks] IPCop and pfSense...

[nate at portents.com]

> How do you determine which CF cards properly support DMA?  Booting from
> CF has been very annoying for me.

Well, I looked into a little more, and apparently it depends on *both* the
CF adapter *and* the CF card:

http://www.fastsilicon.com/storage-reviews/addonics-adsahdcf-sata-cf-adapter-review-3.html

"One area where Addonics could do us all a favor, is in providing a list
of actual Compact Flash devices they recommend to work with their
adapters. Don't misunderstand my caution here, as we ran into no issues
here with actual CF card compatibility. The real issue revolves around
whether or not the Compact Flash card you'd choose to use supports 'UDMA
Fixed Disk Mode' or not. For the most flexibility you're going to want a
device that behaves as a Fixed Disk, and it's here where Addonics could do
their customers a little favor and help them sort through the choices
available and give some recommendations. They had to have done Q&A testing
of their devices on a lot of CF drives, or so you'd think."

> One option could be to adjust a LiveCD to boot from a flash drive and
> run from a ramdisk.  This would leave less memory free for cache usage
> (or require more RAM, but I think you said you were already maxing
> that), but it would remove some of the problems of PIO mode.

Yeah, I've been thinking about that, and it's probably a good idea in
general with flash media to minimize writes (turn off swap, and log to RAM
then dump to flash at reboot/shutdown).  I know modern flash with
level-wearing is a lot better, but it will still wear out.

- Nate