Klaus Strebel wrote:
> Blair Barnett wrote:
>> I have a simple shell script that writes numbers to a file and every 10
>> numbers does a sync and after 40 does a reboot. I've attached the script
>> to this email.
>>
>> If the file is written to an EXT3 filesystem, then file contains the
>> numbers 1-40. However, if the file is written to an XFS 1.1,1.2, or 1.3
>> filesystem, then file contains the numbers 1-10.
>>
>> Can someone tell me if this is a feature of XFS or a bug?
> your in danger do get flamed ;-) though:
>
> The man-page of mount states in the options for ext3:
[snip]
> So, your ext3 does a data=ordered (if you didn't change it, obviously
> you didn't, you would have known the man-page ;-) ), while xfs's
> behaviour is more like data=writeback. In special circumstances this can
> even lead to data loss on xfs (see a thread in linux-xfs@xxxxxxxxxxx,
> metadata is written, extents for the file are zeroed out but data's not
> written to, well should almost never happen in actual CVS kernel ;-)).
What buffles me a bit is that he does a "reboot -f" and, according to the
man page on my RedHat 7.3 system, reboot should sync the filesystems
prior to reboot. If he'd done a "reboot -fn" (-n = don't sync) then I'd
expect this, though.
Cheers,
Juri
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