On Aug 19, 2009 09:17 -0400, Josef Bacik wrote: > > - does this guarantee also hold for remote filesystems (nfs / smb) ? > > This I'm more likely to be wrong on, but I don't think so. It would be atomic > on the local machine, but if there is somebody else on another machine writing > to the same file I think you would probably be screwed. With NFS at least, there is absolutely no guarantee of any kind when multiple clients write to the same file, even with non-overlapping writes (i.e. no O_APPEND, but application seeks to different file offsets). That is because an NFS client does not necessarily flush its local cache until it closes the file. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html