On Mon, May 25, 2020 at 01:23:54PM +1000, Dave Chinner wrote: > On Wed, May 20, 2020 at 03:15:10PM +0200, Emmanuel Florac wrote: > > Le Wed, 20 May 2020 11:14:30 +1000 > > Dave Chinner <david@xxxxxxxxxxxxx> écrivait: > > > > > Well, there's a difference between what a distro that heavily > > > patches the upstream kernel is willing to support and what upstream > > > supports. And, realistically, v4 is going to be around for at least > > > one more major distro release, which means the distro support time > > > window is still going to be in the order of 15 years. > > > > IIRC, RedHat/CentOS v.7.x shipped with a v5-capable mkfs.xfs, but > > defaulted to v4. That means that unless you were extremely cautious > > (like I am :) 99% of RH/COs v7 will be running v4 volumes for the > > coming years. How many years, would you ask? > > Largely irrelevant to the question at hand, as support is dependent > on the distro lifecycle here. Essentially whatever is in RHEL7 is > supported by RH until the end of it's life. > > In RHEL8, we default to v5 filesystems, but fully support v4. That > will be the case for the rest of it's life. Unless the user > specifically asks for it, no new v4 filesystems are being created on > current RHEL releases. > > If we were to deprecate v4 now, then it will be marked as deprecated > in the next major RHEL release. That means it's still fully > supported in that release for it's entire life, but it will be > removed in the next major release after that. So we are still > talking about at least 15+ years of enterprise distro support for > the format, even if upstream drops it sooner... We probably ought to do it sooner than later though, particularly if we think/care about 5.9 turning into an LTS. > > As for the lifecycle of a filesystem, I just ended support on a 40 TB > > archival server I set up back in 2007. I still have a number of > > supported systems from the years 2008-2010, and about a hundred from > > 2010-2013. That's how reliable XFS is, unfortunately :) > > Yup, 10-15 years is pretty much the expected max life of storage > systems before the hardware really needs to be retired. We made v5 > the default 5 years ago, so give it another 10 years (the sort of > timeframe we are talking about here) and just about > everything will be running v5 and that's when v4 can likely be > dropped. > > The other thing to consider is that we need to drop v4 before we get > to y2038 support issues as the format will never support dates > beyond that. Essentially, we need to have the deprecation discussion > and take action in the near future so that people have stopped using > it before y2038 comes along and v4 filesystems break everything. > > Not enough people think long term when it comes to computers - it > should be more obvious now why I brought this up for discussion... Ok then, who would like to help me get the y2038 timestamp patches reviewed for ~5.9? :D (Anyone; not necessarily Dave) --D > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx
