On Tue, 2004-12-14 at 09:32 -0600, John Goerzen wrote: > Is there any practical way I could try to address this? I would rather > have the files truncated, or even re-linked to /lost+found or something, > than have them contain bad data. I also never seemed to encounter this > behavior with either ext2 or ext3. Was I just lucky, or is there > something fundamentally different about JFS?
I'm not sure how I would address this in jfs. I don't know about ext3, but jfs will create and commit a transaction to create a file as soon as it is opened. What you want is that no transaction gets committed until the file is closed. That would be nearly impossible in jfs since the transaction creating the file modifies the containing directory, and we can't hold up pending changes to the directory if other files are being created before the file is closed. Mounting with -osync would definitely help, but that would really hurt performance. (jfs doesn't fully support the -osync flag, but it will help in the normal write path.) Similarly, tuning /proc/sys/vm/dirty_writeback_centisecs and /proc/sys/vm/dirty_expire_centisecs should reduce the number of files affected, but may adversely affect performance as well. > As for the .so files, I was running apt-get dist-upgrade at the time, so > they were being created/modified at the time of crash; it was just the > magnitude of the problem that was startling, especially given that dpkg > first unpacks things with a temporary filename, then renames them to > their permanent name to try to avoid any corruption in cases like this. > > I don't know if it does a fsync(), though. Actually, I think dpkg does call fsync. I'm not too familiar with debian, but I wonder whether dpkg unpacks the .so files, or if they get dynamically created by ld. I wouldn't expect the files to contain holes if they were simply unpacked and renamed. Are the .so files the only ones with the problem? Shaggy -- David Kleikamp IBM Linux Technology Center _______________________________________________ Jfs-discussion mailing list [EMAIL PROTECTED] http://www-124.ibm.com/developerworks/oss/mailman/listinfo/jfs-discussion
