>>> people aren't objecting to better documentation, they are objecting to >>> misleading documentation. >>> >> Actually Ric is. He's trying hard to make RAID5 look better than it >> really is. > > I object to misleading and dangerous documentation that you have > proposed. I spend a lot of time working in data integrity, talking and > writing about it so I care deeply that we don't misinform people. Yes, truth is dangerous. To vendors selling crap products. > In this thread, I put out a draft that is accurate several times and you > have failed to respond to it. Accurate as in 'has 0 information content' :-(. > The big picture that you don't agree with is: > > (1) RAID (specifically MD RAID) will dramatically improve data integrity > for real users. This is not a statement of opinion, this is a statement > of fact that has been shown to be true in large scale deployments with > commodity hardware. It is also completely irrelevant. > (2) RAID5 protects you against a single failure and your test case > purposely injects a double failure. Most people would be surprised that press of reset button is 'failure' in this context. > (4) Data loss occurs in non-journalling file systems and journalling > file systems when you suffer double failures or hot unplug storage, > especially inexpensive FLASH parts. It does not happen on inexpensive DISK parts, so people do not expect that and it is worth pointing out. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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
