On 2010-08-03 08:03:33 -0500, Les Mikesell wrote: > A filesystem snapshot should present exactly the same scenario as a > machine that lost power or crashed for some similar reason at that > moment, so the question boils down to whether subversion can recover > sensibly from a crash at any point.
Not exactly: in case of a power loss or a kernel crash, the file system can become inconsistent. I think you mean something like: [...] that lost power or crashed while it wasn't writing to the disk. > The fsync's are going to be the critical thing for ordering > operations at the disk level, however there is no guarantee how much > of the fsync operation might have completed when a crash or snapshot > happens. It depends on whether the filesystem snapshot software takes kernel buffers into account or not. And one can assume that the snapshot isn't taken in the middle of a fsync. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)
