On Mon, May 09, 2011 at 01:22:42PM +0800, Emmanuel Noobadmin wrote: > On 5/6/11, Keld Jørn Simonsen <keld@xxxxxxxxxx> wrote: > > Hi List > > > > based on the recent discussion, that showed lacking knowledge > > on Linux MD RAID10 features, I have some thoughts: > > > > It is really hard to disseminate information on "new" features > > in MD RAID. RAID10 has been in the kernel since 2.6.9 - from 2004. > > I have tried to give info on RAID10 at a number of web pages, > > and still many people, even on our linux-raid list are not aware > > of it. > > > > Also many people are confused about Linux MD raid10 and RAID1+0. > > > > So I think we shopuld rather name things in another way. > > > > I would like linux MD raid10 functionality to be part of the Linux MD > > RAID1 module, and be called raid1. This is in accordance with the > > use of the RAID1 term as standadized by SNIA. In fact the RAID10-offset > > layout is an implementation of a SNIA RAID specification. The RAID10-near > > layout is an implementation of a simple RAID layout. And the RAID10-far > > layout is just another layout far a mirrored RAID. So all these types > > could just be defined as different RAID1 layouts. > > Giving my noob's 2 cents worth although I haven't followed the > original discussion. As a noob, I think doing this will just confuse > us more. > > There are plenty of existing materials around for those of us who try > to figure things out by googling. As it is, our (or maybe just me) > understanding is Linux RAID 1 is just like every other raid 1: simple > and straightforward, 2 drives mirroring each other. > > This is is also usually the level that most of us start with. If the > instructions are short, easy to understand and simple to implement, we > usually gain confidence in using it and exploring mdraid further. > > Most of us noobs are also aware that RAID 10 is more complicated and > there are two versions, i.e. 1+0 and 0+1. So psychologically, I had no > problems accepting that once I looked into it, there were much more > complex stuff and all these possible layouts: mdraid is cool! > > Now, if RAID 10 was renamed to RAID 1, with the corresponding change > in documentation, what's going to happen for us noobs is this: "Omg, > why are there so many different versions and options just for raid 1?" > and importantly "Why is this manual/wiki different from the tons of > other pages about using mdraid 1?" For some, this would mean mdraid is > too difficult even for raid 1, mdraid is not cool! :) > > So newbies will get more confused/frustrated as a result. > > Personally, I had to spend some time figuring out (I'm noob and I'm > not very smart) the different layouts from the examples on wiki. This > is because there wasn't enough examples, at least to me, to clearly > show what's the difference if more/less disks were used. So for me, > and other noobs, it would probably help if the wiki had more examples > of each layout, maybe graphics to show the difference since it's > probably easier to see things if they were colour coded blocks rather > than stuff like A1 a1 A2 a2. > > This and perhaps more elaboration on the difference between mdraid 10 > and normal raid 10 would probably be better to clear up confusion > than renaming something we might have some familiarity with, into > something we also already have familiarity, resulting in something > that contradicts existing familiarity. I see your point. Given Neil's input I think we should rateher call it raid1e. Best regards keld -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
