On Tue, Dec 30, 2008 at 09:55:57AM +0300, Alex Tomas wrote: > one good thing about JBD is that you can't update target block and csum > atomically. so, either you use some form of COW or you use journalling. > given we already have JBD it'd make sense to use it? I'm sorry, but I'm not following. Is that first sentence right? The main disadvantage I see of using jbd at the moment is that I loose the possibility of having checksums and data in a different device. The only alternative to jbd that I have at the moment is the "two metadatas" approach I explained in another email (but please let me know if it wasn't clear). They both provide what I need (atomicity in data and csum writes), one is easier, more tested, but prevents a feature. The other is a bit more difficult, untested and written my me, but allows a feature. I have no idea, performance-wise, how they will behave (it is expected they suck, according to the other emails). At this moment I'm going with the two metadatas approach, because I think it has less limitations and it'd be fun to write. If then it's unfit for some reason, I can always go back and use jbd. But I'm obviously open to suggestions and more alternatives. Thanks a lot, Alberto -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
