Messages in this thread | | | Date | Wed, 16 Jun 2004 10:34:35 +0300 | From | Oleg Drokin <> | Subject | Re: mode data=journal in ext3. Is it safe to use? |
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Hello!
Petter Larsen <pla@morecom.no> wrote:
PL> Can anybody of you acknowledge or not if mode data=journal in ext3 is PL> safe to use in Linux kernel 2.6.x? PL> Wee need to have a very consistent and integrity for our filesystem, and PL> it would then be desired to journal both data and metadata.
Actually data=journal mode would gain you mostly zero extra consistency compared to data=ordered mode. (the only more consistency bit that you get is correct mtime on files that have their pages overwritten, I think). You have zero control over transaction boundaries in ext3, so you still need to design your applications in such a way that they have their own sort of transactions (if this is needed).
PL> Data integrity is much more important for us than speed.
It is not clear what sort of extra data integrity do you expect from data journaling mode and why do you think it is there.
Garbage in files should not happen in data ordered mode as data pages are written first before metadata updates are committed.
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