Hi, there was recently a bug reported against EXT4 that gets triggered by KDE: https://bugs.edge.launchpad.net/ubuntu/+source/linux/+bug/317781
Now I'd like to verify that my understanding of ZFS behavior and implementations is correct, and ZFS is unaffected from this kind of issue. Maybe somebody would like to comment on this. The underlying problem with ext4 is that some kde executables do something like this: 1a) open and read data from file x, close file x 1b) open and truncate file x 1c) write data to file x 1d) close file x or 2a) open and read data from file x, close file x 2b) open and truncate file x.new 2c) write data to file x.new 2d) close file x.new 2e) rename file x.new to file x Concerning case 1) I think ZFS may lose data if power is lost right after 1b) and open(xxx,O_WRONLY|O_TRUNC|O_CREAT) is issued in a transaction group separately from the one containing 1c/1d. Concerning case 2) I cannot see ZFS losing any data, because of copy-on-write and transaction grouping. Theodore Ts'o (ext4 developer) commented that both cases are flawed and cannot be supported correctly, because of a lacking fsync() before close. Is this correct? His comment is over here: https://bugs.edge.launchpad.net/ubuntu/+source/linux/+bug/317781/comments/54 Any thoughts or comments? TIA, Thomas _______________________________________________ opensolaris-discuss mailing list opensolaris-discuss@opensolaris.org
