Hi Caitlin, I'm interested in ZFS support in Swift.
lfszfs.py in your patch imports "nspyzfs", but I could not find it. Where can I get it from? > The first patch has been posted for review: > > https://github.com/vineethrp/swift/commit/c062d4bad5fd8aa4a7bc5ad481b23c07216f281a > > This patch creates the LocalFS class, and includes a default when no enhanced > LocalFS > has been installed. Nexenta is developing the ZFS version for the LocalFS, > and the first > version is in the above patch. Others could implement the same capabilities > over other > file systems. Regards, Akihiro MOTOKI >>>>> Date: Fri, 21 Oct 2011 18:04:57 +0000 >>>>> From: Caitlin Bestler <caitlin.best...@nexenta.com> >>>>> Subject: [Openstack] First patch for LocalFS enhancement available for >>>>> review > > The LocalFS proposal was first posted a month ago, which is quoted below. > > To quickly recap the purpose is to enable enhanced Object Servers that provide > features such as self-healing mirrors, which can achieve the same availability > with fewer network replications being required. Read the blueprint for > details. > > Specifically, Nexenta is interested in enabling use of ZFS self-healing > mirroring. > A replica produced by the ZFS file system does not consume network bandwidth, > But unlike conventional simple disk mirroring, ZFS self-healing mirroring > will detect > and heal latent disk errors. > > Relying on self-healing mirroring essentially makes a replica with local IO > bandwidth > rather than with network bandwidth. Physically the replicas are just as > independent > as a network replica. > > A deployment that has two network replicas, that each have two local copies, > should > provide superior availability than three network replicas. The superior > availability also > comes with reduced consumption of network bandwidth. Further, there would be > no > degradation in transaction latency. > > The first patch has been posted for review: > > https://github.com/vineethrp/swift/commit/c062d4bad5fd8aa4a7bc5ad481b23c07216f281a > > This patch creates the LocalFS class, and includes a default when no enhanced > LocalFS > has been installed. Nexenta is developing the ZFS version for the LocalFS, > and the first > version is in the above patch. Others could implement the same capabilities > over other > file systems. > > > There is one major issue that the concept of self-healing mirrors introduces. > Basically > a replica of a partition can be in a degraded state when the full set of > mirrors are not up. > Obviously such a replica will probably need to be replicated, but unlike an > unmirrored > replica that has had a drive failure it is not useless. We suspect that a > lower priority > replication is the correct response, but this is something that should be > discussed > by the team as a whole. > > > On 09/15/2011 10:18 AM, Caitlin Bestler wrote: > > Greetings, > > > > A blueprint has been submitted for an extension to enable Local File > > Systems to take responsibility for > > certain operations, allowing generic Swift code to offload some burdens > > when these optional capabilities > > are available. > > > > The goal of this proposal is to allow an Object Server to take advantage of > > the capabilities of the ZFS > > file system, but it could be applied for other enhanced file systems as > > well. > > > > The blueprint is: https://blueprints.launchpad.net/swift/+spec/localfs > > The etherpad description is: http://etherpad.openstack.org/YMTqYzPmZQ > > > > This is the first of what will probably be a handful of proposals from > > Nexenta Systems, all with the goal > > of enabling value added Object Servers. > > > > So we should introduce ourselves. > > > > Nexenta brings open source solutions built on ZFS to provide software-based > > NAS/SAN appliances. The core value of the ZFS file system is delivered in > > an enterprise class storage solution. We intend to bring the value of ZFS > > as a local file system to Cloud Storage as well. > > > > >From http://en.wikipedia.org/wiki/ZFS > > > > In computing, ZFS is a combined file system and logical volume manager > > designed by Sun Microsystems. The features of ZFS include data integrity > > verification against data corruption modes (like bit rot), support for high > > storage capacities, integration of the concepts of filesystem and volume > > management,snapshots and copy-on-write clones, continuous integrity > > checking and automatic repair, RAID-Z and native NFSv4 ACLs. ZFS is > > implemented as open-source software, licensed under the Common Development > > and Distribution License (CDDL). The ZFS name is a trademark of Oracle.[3] > > > > > > > > To take advantage of ZFS capabilities we will need to work with the Swift > > project to define how the core Swift code discovers and exploits optional > > capabilities. This is a role similar to that of a graphics chip or network > > interface vendor working with an open source OS project. The goal is to > > enable enhanced functionality with interfaces that make the enhanced > > functionality optional and largely vendor neutral. Other file system > > providers should be able to plug-in in their own solutions. > > > > Nexenta appliances are based on open source operating system that utilizes > > OpenSolaris, in a near future - Illumos, kernel. This means we will end up > > testing that the python code is truly OS independent, and we anticipate > > submitting a steady but hopefully small stream of patches to fix code that > > was inadvertently Linux dependent. The goal will be to supply patches that > > make the code truly generic, and hopefully avoid just accumulating any "if > > linux elif illumos elif bsd ..." sequences in Swift code. > > > > >From http://en.wikipedia.org/wiki/Illumos: > > > > Illumos is a derivative of OS/Net (aka ON), which basically is a > > Solaris/OpenSolaris kernel with the bulk of the drivers, core libraries, > > and basic utilities. It is dependent on OS/Net, which Illumos will follow > > very closely while allowing to retain changes to code which might be > > unacceptable to upstream OpenSolaris. Illumos is aiming at 100% ABI > > (Application Binary Interface) compatibility with Solaris ON, focusing just > > on the core foundation blocks. > > > _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
