On Tue, Jun 09, 2015 at 03:08:11PM -0500, Goldwyn Rodrigues wrote: > Hi David, > > On 06/09/2015 02:45 PM, David Teigland wrote: > >On Tue, Jun 09, 2015 at 02:26:25PM -0500, Goldwyn Rodrigues wrote: > >>On 06/09/2015 01:22 PM, David Teigland wrote: > >>>I've just noticed the existence of clustered MD for the first time. > >>>It is a major new user of the dlm, and I have some doubts about it. > >>>When did this appear on the mailing list for review? > >> > >>It first appeared in December, 2014 on the RAID mailing list. > >>http://marc.info/?l=linux-raid&m=141891941330336&w=2 > > > >I don't read that mailing list. Searching my archives of linux-kernel, it > >has never been mentioned. I can't even find an email for the md pull > >request that included it. > > Is this what you are looking for? > http://marc.info/?l=linux-kernel&m=142976971510061&w=2
Yes, I guess gmail lost it, or put it in spam. > >- "experimental" code for managing md/raid1 across a cluster using > > DLM. Code is not ready for general use and triggers a WARNING if > > used. However it is looking good and mostly done and having in > > mainline will help co-ordinate development. > > > >That falls far short of the bar for adding it to the kernel. It not only > >needs to work, it needs to be reviewed and justified, usually by showing > > Why do you say it does not work? It's just my abbreviation of that summary paragraph. > It did go through it's round of reviews on the RAID mailing list. I > understand that you missed it because you are not subscribed to the raid > mailing list. I will look for that. > >some real world utility to warrant the potential maintenance effort. > > We do have a valid real world utility. It is to provide > high-availability of RAID1 storage over the cluster. The > distributed locking is required only during cases of error and > superblock updates and is not required during normal operations, > which makes it fast enough for usual case scenarios. That's the theory, how much evidence do you have of that in practice? > What are the doubts you have about it? Before I begin reviewing the implementation, I'd like to better understand what it is about the existing raid1 that doesn't work correctly for what you'd like to do with it, i.e. I don't know what the problem is. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
