Coda File System

Re: venus startup fails; ramfs and coda

From: Christopher J Mason <>
Date: Tue, 19 Sep 2000 13:39:29 -0400
--On 09/19/00 01:25:11 PM -0400 Laszlo Vecsey <> wrote:

> I'm curious to know how the -rvmt 3 option works for you on this portable
> device. I'm currently using venus on a diskless client but with the RVM
> storage since I didn't have any success with this option.
> 6 years of bit-rot.. what oh what has changed.

I'll certainly try it tonight.

Seems like the "right way" to do it for this device (which has 16 mb of 
flash memory) would be to write the log in a raw flash partition.  This way 
if you lost battery power while disconnected, you would still have your 

But this probably takes some intelligence begin built into RVM.  Flash has 
properties which are quite different from either RAM or disk.  Erases take 
a long time (on the order of seconds), and you have to erase a whole sector 
to set any of the bits to 0, but you can set bits to 1 without erasing. 
You can use this for flags and whatnot.  You also want to spread the erases 
out evenly over the flash because flash wears out after around 100,000 
erase cycles.  Maybe RVM could be made to take advantage of these 

I'd like to get it working at all first. ;-)


[Christopher Mason        <> ]
["Don't you see?! We're actors--we're the opposite of people!" -Stoppard]
Received on 2000-09-19 13:40:45