Subject: Re: wd, disk write cache, sync cache, and softdep.
To: Daniel Carosone <email@example.com>
From: Charles M. Hannum <firstname.lastname@example.org>
Date: 12/16/2004 23:30:11
On Thursday 16 December 2004 23:23, Daniel Carosone wrote:
> Finally, it's about getting the most out of cheap hardware - not just
> the most performance but the most reliability as well.
I have to conclude from this that you actually don't understand the real
problems at all. To whit:
* You can lose critical file system data (say, the root inode) just by turning
off the power in the middle of a write. Fixing this properly really
*requires* journaling. As Jason mentioned, your journaling system can take
care of the write ordering during flushing (and without much performance
* There are other reliability problems, some of which were mentioned in recent
(albeit terse) PRs, that are *much* bigger than the risk from the drive's
You're shooting at the wrong target.