On Sat, 2005-11-12 at 14:54 -0800, Hans Reiser wrote: > David Masover wrote: > > >Ming Zhang wrote: > > > > > >>On Fri, 2005-11-11 at 16:56 -0800, Peter van Hardenberg wrote: > >> > >> > >> > >>>On November 11, 2005 05:59 am, John Gilmore wrote: > >>> > >>> > >>> > >>>>Does anybody remember GoBack? It was a versioning > >>>>system for windows 95/98 that was incredibly flexible and useful. Tracked > >>>>all changes to the whole disk. Old versions of a file? no problem. grab an > >>>>old version of a directory for referance temporarily? easy. Got a virus? > >>>>revert the whole HD, and then grab the newer copies of your documents and > >>>>saved games as needed. > >>>> > >>>> > >>>My thoughts on this: > >>> > >>>The versioning would be an audit plugin. When the file is modified, tag > >>>the > >>>current version, copy it into a sub-directory (oh, I don't know, say > >>>file/.revisions/<number/date>), and disable write access to it. You might > >>>not > >>>even need extended filesystem attributes for this, but they would be handy > >>>for tagging particular versions. > >>> > >>> > >>if a file is opened, modified 2 times, then closed. u will only generate > >>1 version right? so "When the file is modified" is inaccurate. > >> > >> > one could do it for every file close, and that could be a state option > for the versioning plugin, but most users will want to do it everytime > they touch filename/..../checkin
what u mean touch filename? is "ls" a touch? i think close, unlink, create, is likely to be good candidate. > > > > >How about "When the transaction was completed?" Why does it matter? > > > > > > > >>>Copy-on-write would make this action extremely cheap, only adding a couple > >>>of > >>>extra writes to make it work. > >>> > >>> > >>add 1 line at the beginning of a 100MB text file will make this uncheap. > >> > >> > > > >Who has to work with 100 meg text files? And why has this person not > >broken them down into 100 kilobyte text files? Storage efficiency isn't > >really an issue there... > > > > > you need cross-version compression for this case. what u mean cross-version compression? interesting name. :P ming > > >Anyway, I think the main win is from copy-on-write for the whole file. > > > > > > > > > > >
