公开(公告)号：US11449239B2

公开(公告)日：2022-09-20

申请号：US17001294

申请日：2020-08-24

Applicant: NetApp, Inc.

Inventor： Randolph Sterns ,  Charles Binford ,  William Delaney ,  Joseph Blount ,  Keith Moyer ,  Joseph Moore

IPC: G06F11/00 ,  G06F3/06 ,  G06F11/14

Abstract: A system for tracking metadata changes and recovering from system interruptions. With host I/O, corresponding metadata incremental changes are aggregated and stored in a write-ahead log before being performed to their in-memory buffers. As those buffers are flushed, checkpoints are created and stored in the log. As the log wraps to the start, older entries are overwritten after they are freed from any remaining dependencies by newer checkpoints. If metadata entities have not created new checkpoints, they are instructed to in order to free up space for new aggregated batches and checkpoints. After an interruption, the wrap point is located in the log. From the wrap point, the log is scanned backwards to provide checkpoints to metadata entities. The log is then scanned forwards to perform changes specified by aggregated batches. The metadata entities' volatile memory states are recovered to what they were before the interruption.

公开(公告)号：US20220027048A1

公开(公告)日：2022-01-27

申请号：US17495626

申请日：2021-10-06

Applicant: NETAPP, INC.

Inventor： Joseph Blount

IPC: G06F3/06 ,  G06F12/02

Abstract: A system and method for improving storage system performance by reducing or avoiding load spike amplification when performing garbage collection is disclosed. A storage controller in a storage system tracks system load including write load and read load, as well as available free segments. The storage controller uses these tracked values as inputs and, with these inputs, generates a garbage collection rate. Where read load is included, a scaled portion of the read load is taken into consideration so that, as the number of free segments nears the minimum amount desired and to prevent garbage collecting too slowly, the read load is gradually excluded from the garbage collection rate determination. The garbage collection rate is therefore responsive to system load so that, in times of high system load, the rate reduces as much as is safe so that the write load takes priority with computing resources of the storage controller.

公开(公告)号：US09990261B2

公开(公告)日：2018-06-05

申请号：US15142999

申请日：2016-04-29

Applicant: NetApp, Inc.

Inventor： Joseph Blount ,  William P. Delaney ,  Charles Binford ,  Joseph Moore ,  Randolph Sterns

IPC: G06F11/16 ,  G06F11/20 ,  G06F3/06 ,  H04L29/08 ,  G06F11/10

CPC classification number: G06F11/2069 ,  G06F3/0619 ,  G06F3/065 ,  G06F3/0689 ,  G06F11/1092 ,  G06F2201/805 ,  G06F2211/104 ,  H04L67/1097

Abstract: Systems and techniques for recovering a storage array are disclosed. These systems and techniques include determining a size corresponding to a storage stripe of the storage array. Pieces assigned to the storage stripe are identified. A storage configuration corresponding to the pieces assigned to the storage stripe is detected. Ordinal information and parity information are determined corresponding to the pieces assigned to the storage stripe. The size determined corresponding to the storage stripe, identification of the pieces assigned to the storage stripe, the storage configuration, the ordinal information, and the parity information is stored in a data store to reconstruct lost or corrupted metadata corresponding to the storage array.

公开(公告)号：US09830107B2

公开(公告)日：2017-11-28

申请号：US15142923

申请日：2016-04-29

Applicant: NetApp, Inc.

Inventor： Joseph Blount

IPC: G06F3/06

CPC classification number: G06F3/0649 ,  G06F3/0616 ,  G06F3/0631 ,  G06F3/0632 ,  G06F3/0644 ,  G06F3/0679 ,  G06F3/0688 ,  G06F3/0689

Abstract: A system and method for optimizing the estimation and management of wear and replacement for an array of storage devices in a storage system is disclosed. An input/output workload is monitored over part of a service period for the array. An expected wear rate is determined, based on the workload and an endurance of the storage devices. A target wear rate is calculated for the service period and each of one or more contingency periods, based on the expected wear rate and a specified risk tolerance for each period. In response to determining that the expected wear rate exceeds the target wear rate calculated for at least one of the service period and the contingency period(s), an adjusted wear rate is calculated for the array of storage devices to match the target wear rate. A replacement schedule is generated for the array based on the adjusted wear rate.

公开(公告)号：US20170316041A1

公开(公告)日：2017-11-02

申请号：US15142828

申请日：2016-04-29

Applicant: NetApp, Inc.

Inventor： William P. Delaney ,  Joseph Blount ,  Charles Binford ,  Joseph Moore ,  Randolph Sterns ,  Jeff Stilger

IPC: G06F17/30

CPC classification number: G06F16/2246 ,  G06F16/2237 ,  G06F16/9017

Abstract: A method for mapping a first address space to a second address space is provided. In some embodiments, the method includes creating a first array of lookup entries and one or more second arrays of metadata entries for maintaining an ordering among the lookup entries using a tree structure. Each of the metadata entries includes one or more data index values identifying a corresponding one of the lookup entries by its position in the first array and one or more metadata index values identifying a corresponding one of the metadata entries by its position in one of the one or more second arrays. The method further includes receiving a request including a lookup value, traversing the tree structure to locate a lookup entry corresponding to the lookup value, and when the lookup value is located among the lookup entries, using the located lookup entry to process the request.

公开(公告)号：US20170315753A1

公开(公告)日：2017-11-02

申请号：US15142923

申请日：2016-04-29

Applicant: NetApp, Inc.

Inventor： Joseph Blount

IPC: G06F3/06

CPC classification number: G06F3/0649 ,  G06F3/0616 ,  G06F3/0631 ,  G06F3/0632 ,  G06F3/0644 ,  G06F3/0679 ,  G06F3/0688 ,  G06F3/0689

Abstract: A system and method for optimizing the estimation and management of wear and replacement for an array of storage devices in a storage system is disclosed. An input/output workload is monitored over part of a service period for the array. An expected wear rate is determined, based on the workload and an endurance of the storage devices. A target wear rate is calculated for the service period and each of one or more contingency periods, based on the expected wear rate and a specified risk tolerance for each period. In response to determining that the expected wear rate exceeds the target wear rate calculated for at least one of the service period and the contingency period(s), an adjusted wear rate is calculated for the array of storage devices to match the target wear rate. A replacement schedule is generated for the array based on the adjusted wear rate.

公开(公告)号：US20170308303A1

公开(公告)日：2017-10-26

申请号：US15135161

申请日：2016-04-21

Applicant: NetApp, Inc.

Inventor： Randolph Sterns ,  Charles Binford ,  William P. Delaney ,  Joseph Blount ,  Reid Kaufmann ,  Joseph Moore

IPC: G06F3/06 ,  G06F11/10

Abstract: A method includes: storing a first data extent on a physical medium, wherein the physical medium is divided into a plurality of storage blocks, wherein each of the storage blocks has a size that is different than a size of the first data extent, further wherein the first data extent is stored to a first block of the plurality of storage blocks; generating a descriptor for the first data extent, wherein the descriptor indicates that the first data extent starts within the first block of the plurality of blocks and indicates an offset from the beginning of the first block at which the first data extent starts; and storing the descriptor within the first block.

公开(公告)号：US20170220249A1

公开(公告)日：2017-08-03

申请号：US15011050

申请日：2016-01-29

Applicant: NetApp, Inc.

Inventor： Mahmoud K. Jibbe ,  Jeff Hudson ,  Joseph Blount ,  Keith Holt

IPC: G06F3/06 ,  G06F12/08

CPC classification number: G06F12/0806 ,  G06F11/0727 ,  G06F11/1076 ,  G06F11/20 ,  G06F2212/621

Abstract: Embodiments of the present disclosure enable high availability and performance in view of storage controller failure. A storage system includes three or more controllers that may be distributed in a plurality of enclosures. The controllers are in high availability pairs on a per volume basis, with volumes and corresponding mirror targets distributed throughout the storage system. When a controller fails, other controllers in the system detect the failure and assess whether one or more volumes and/or mirror targets are affected. If no volumes/mirror targets are affected, then write-back caching continues. If volume ownership is affected, then a new volume owner is selected so that write-back caching may continue. If mirror target ownership is affected, then a new mirror target is selected so that write-back caching may continue. As a result, write-back caching availability is increased to provide low latency and high throughput in degraded mode as in other modes.