-- Erik B. Andersen Web: http://www.inconnect.com/~andersen/ email: andersee@debian.org --This message was written using 73% post-consumer electrons--
On Tue, 22 Jul 1997, Rogier Wolff wrote:
> Colin Plumb wrote: > > > > Looking at reiserfs, I found a University of Michigan tech report > > on "soft updates" a technique to remove all synchronous writes > > from a file system yet maintain fsck-less crashes. > > > > (By always marking data in use before it's used and ensuring that > > data is not used before it's marked free, a crash can leave some > > If you first mark a block as used, and only then write the block, > the filesystem won't be corrupt when the system crashes inbetween. > However, your DATA will be corrupt. > > I think it's better to have fsck detect a broken filesystem, than to > have a file silently contain bad data. As far as I know, Linus also > thinks this way. > > You also eliminate the possibility of reordering writes at the > driver or drive level. (e.g. "tagged queuing" is forbidden...) > > All this would be very hard to debug: You'd have to try throwing > the switch on your system quite a few times to be sure it works. > > Roger. > > >