Oracle International Corporation

David Friedman

Prasad V Bagal

Juan R Loaiza

Kothanda Umamageswaran

Jia Shi

Alex Tsukerman

Harish Nandyala

Zuoyu Tao

Rajiv Wickremesinghe

William Havinden Bridge, Jr

Richard L Long

Boris Erlikhman

No-loss rapid recovery performs resynchronization efficiently while concurrently allowing availability to mirrored data on the storage device. No-loss rapid recovery has two stages and involves storage devices that have both a non-volatile cache and primary storage and that operate as mirror buddies. The first stage is referred to herein as the buddy-retention stage. During the buddy-retention stage, writes to mirrored data are not performed on the offline mirror buddy but are performed on the online mirror buddy. The mirrored data changed in the online mirrored buddy is retained in the non-volatile cache of the retention buddy. The next stage is referred to herein as the rapid resynchronization stage. In this stage, the changed mirrored data retained by the retention buddy for no-loss rapid recovery is used to resynchronize the offline buddy. The storage device is resynchronized using the changed mirrored data retained in the cache of the mirror buddy.

Rapid recovery from downtime of mirrored storage device

A method and apparatus for booting a clustered management system is provided where the configuration information required to boot the system is stored within the system itself. The techniques cope with several issues including finding the configuration data on the physical disk before the logical disk system is established, coping with replicated copies of configuration data, network partitions and disk drive failures that may prevent a booting node to have perfect knowledge of the state of the entire system, and active nodes modifying or moving configuration data while the booting node is searching for a consistent, correct copy of configuration data.

Bootstrapping server using configuration file stored in server-managed storage

Dirty data in a storage device is made current through rapid re-silvering, which uses a mirrored and up-to-date version of the dirty data from another storage device to recover the data. Because under rapid re-silvering cache metadata in volatile memory survives the failure of the cache, the cache metadata is used to determine which subset of data from the other storage device needs to be copied to the storage device being re-silvered. During re-silvering, cache metadata is used to determine which I/O requests from clients are requests for data that is not stale.

Rapid recovery from loss of storage device cache

A method of updating an extent map is described. The method includes providing in a memory an instance of a first version of the extent map, wherein the instance is referenced by an application. The extent map include entries. The method further includes storing, at each extent map entry, an offset from the beginning of a physical drive which is identified within said each extent map entry, providing a second version of the extent map, comparing the first version of the extent map with the second version of the extent map, in response to the comparing, determining that is at least on segment in the second version of the extent map that is different from a corresponding at least one segment in the first version of the extent map.

Efficient volume manager hot swapping

Methods of hot-swapping a logical volume manager (LVM) and updating an associated extent map are presented. Methods for migrating a virtual machine running an application using an LVM from one physical machine to another physical machine are also presented. The LVM can be used by a database application or other applications in a single-node or multi-node environment. The LVM is shut down, version numbers for each segment of its associated extent map are saved, and a new LVM is started. The new LVM's extent map is compared with the old extent map, and segments in the LVM which have changed are selectively updated.

Embodiments of the present invention enable dynamic repartitioning of data storage in response to one or more triggers. In embodiments, a trigger may be a user-initiated action, a system-generated action, and/or an inference based on storage usage parameters. Applications of the present invention are its use in embodiments of a storage management system comprising a file system manager and a volume manager, where the placement of data into a partition (data storage region) may be specified by matching one or more disk region placement data attributes assigned to data with corresponding disk region attributes. In embodiments, dynamic repartitioning comprises adjustment of the location of the boundary between adjacent disk partitions and, if necessary, rebalancing of the data stored within the partitions by identifying mismatched data and relocating it to the partition with which it is associated.

Growing community of inventors

New York, NY, United States of America

David Friedman