公开(公告)号：US20220350491A1

公开(公告)日：2022-11-03

申请号：US17306424

申请日：2021-05-03

Applicant: EMC IP HOLDING COMPANY LLC

Inventor： Bhaskar Bora ,  Jeffrey Wilson ,  Michael Ferrari ,  William Stronge ,  Sandeep Chandrashekhara

IPC: G06F3/06

Abstract: A target-less point in time image (snapshot) of a storage volume is allowed to be built after activation, by enabling the snapshot data to be modified to create a crash-consistent replica of the source data after the snapshot has been activated. The data of the snapshot remains immutable from a user standpoint, but the snapshot is able to be quickly activated before all of the data of the snapshot has been included in the snapshot, to thus reduce an amount of time IO operations on the source volume are quiesced. A first snapshot of a storage volume is created on a primary storage system and a corresponding second snapshot of the storage volume is activated on a backup storage system before all the data of the first snapshot is received at the backup storage system. Entries of the activated second snapshot are then changed to point to correct back-end allocations.

公开(公告)号：US20220342549A1

公开(公告)日：2022-10-27

申请号：US17237171

申请日：2021-04-22

Applicant: EMC IP Holding Company LLC

Inventor： Ian Adams ,  Bhaskar Bora ,  Jeffrey Wilson

IPC: G06F3/06

Abstract: Snapshots may be remotely replicated asynchronously from a first LSU (R1) on a first storage system (A) to a second replica LSU (R2) on a second storage system (A2). The storage system A1 may open a consistency window to suspend initiating processing of new write operations received on A1. While the consistency window is open, A1 may: take a first snapshot, SS11, of R1; record, in association with the first replication cycle, an indication to replicate SS11 on A2; and initiate a next replication cycle to record write operations of the next new write requests to be received from hosts. After initiating a next replication cycle, A1 may close the consistency and transmit the first replication cycle to A2. A2 may apply the write operations of the first replication cycle to R2, and then take a second snapshot SS12 of R2, which should be a replica of SS11.

公开(公告)号：US11340795B2

公开(公告)日：2022-05-24

申请号：US16885662

申请日：2020-05-28

Applicant: EMC IP Holding Company LLC

Inventor： Jeffrey Wilson ,  Michael Ferrari ,  Mark J. Halstead ,  Sandeep Chandrashekara

IPC: G06F3/06 ,  G06F11/14

Abstract: A snapshot lookup table (SLT) and snapshot pointer structure(s) (SPSs) may be provided for a logical data unit (LSU), each SPS entry corresponding to an LSU data portion and a physical storage location at which data is stored for the data portion for a particular snapshot. A current lookup table (CLT) for a current time may be provided for an LSU, including an entry for each LSU data that points to a respective entry of an SPS. Each time a first write following the creation of a snapshot is made to an LSU data portion, the corresponding CLT entry may be updated to point to the SPS entry that was updated to point to an LSU track table entry. To create a snapshot, a snapshot lookup table (SLT) is created for each snapshot, and the contents of the CLT are copied to the newly created SLT.

公开(公告)号：US11307933B2

公开(公告)日：2022-04-19

申请号：US16805405

申请日：2020-02-28

Applicant: EMC IP Holding Company LLC

Inventor： Jeffrey Wilson ,  Owen Martin

IPC: G06F16/00 ,  G06F11/14

Abstract: Providing automated targetless snapshots for storage volumes includes estimating storage space needed for a new set of the snapshots based on an amount of expected change of data on the storage volumes, deleting current snapshots to free up an amount of space corresponding to estimated storage space for the new set of the snapshots, and creating the new set of the snapshots. The current snapshots may be selected for deletion based on creation date of the snapshots. Snapshots with an oldest creation data may be deleted. The storage volumes may be provided on a storage system. The storage system may show storage space used by the snapshots as unallocated. Storage space used by the snapshots may be managed by a storage resource pool. The storage resource pool may convert storage space shown as unallocated into allocated storage space in response to snapshots provided therein being converted into accessible snapshots.

公开(公告)号：US11275656B2

公开(公告)日：2022-03-15

申请号：US16852785

申请日：2020-04-20

Applicant: EMC IP Holding Company LLC

Inventor： Owen Martin ,  Jeffrey Wilson

IPC: G06F3/06 ,  G06F11/14 ,  G06N20/00 ,  G06N3/08

Abstract: Embodiments of the present disclosure relate to autonomous data protection. One or more input/output (I/O) streams can be received by one or more storage devices. One or more snapshots of each storage device can be obtained. One or more anomalies can be identified based on a change rate corresponding to each storage device's memory allocated to store user data included in the I/O streams.

公开(公告)号：US20220342908A1

公开(公告)日：2022-10-27

申请号：US17237127

申请日：2021-04-22

Applicant: EMC IP Holding Company LLC

Inventor： Bhaskar Bora ,  Deepak Vokaliga ,  Mark J. Halstead ,  Jeffrey Wilson ,  William R. Stronge ,  Ian Adams

IPC: G06F16/27

Abstract: Snapshots from a first LSU (R1) on a first storage system (A1) may be replicated to a second replica LSU (R2) on a second storage system (A2), for example, concurrently to remotely replicating (e.g., synchronously) write operations for R1 to R2. A process, P, on A1 executing the replication of the snapshots from R1 to R2 may be a separate process than the one or more processes on A1 executing remote replication of write operations for R1 to R2. During a consistency window on A1, outstanding write operations for R1 at the time the consistency window opened may be logged, and a pair of snapshots, SS11 and SS12 may be activated on R1 and R2, respectively. After the consistency window has closed, the SS12 snapshot metadata and snapshot data may be updated based on the outstanding write operations.

公开(公告)号：US11467757B1

公开(公告)日：2022-10-11

申请号：US17306424

申请日：2021-05-03

Applicant: EMC IP HOLDING COMPANY LLC

Inventor： Bhaskar Bora ,  Jeffrey Wilson ,  Michael Ferrari ,  William Stronge ,  Sandeep Chandrashekhara

IPC: G06F3/06

Abstract: A target-less point in time image (snapshot) of a storage volume is allowed to be built after activation, by enabling the snapshot data to be modified to create a crash-consistent replica of the source data after the snapshot has been activated. The data of the snapshot remains immutable from a user standpoint, but the snapshot is able to be quickly activated before all of the data of the snapshot has been included in the snapshot, to thus reduce an amount of time IO operations on the source volume are quiesced. A first snapshot of a storage volume is created on a primary storage system and a corresponding second snapshot of the storage volume is activated on a backup storage system before all the data of the first snapshot is received at the backup storage system. Entries of the activated second snapshot are then changed to point to correct back-end allocations.

公开(公告)号：US20220121374A1

公开(公告)日：2022-04-21

申请号：US17072133

申请日：2020-10-16

Applicant: EMC IP HOLDING COMPANY LLC

Inventor： Sandeep Chandrashekhara ,  Michael Ferrari ,  Jeffrey Wilson

IPC: G06F3/06

Abstract: A snapshot for use in a cascaded snapshot environment includes a device level source sequence number and a Direct Image Lookup (DIL) data structure. The device level source sequence number indicates the level of the snapshot in the cascade, and the snapshot DIL indicates the location of the data within the snapshot cascade. A target device for use in the cascaded snapshot environment includes a device level target sequence number, a track level sequence data structure, and a DIL. When the target device is linked to a snapshot, the device level target sequence number is incremented, which invalidates all tracks of the target device. The snapshot DIL is copied to the target device, but a define process is not run on the target device such that the tracks of the target device remain undefined. IO operations use the device level target sequence number to identify data on the target device.

公开(公告)号：US11237916B2

公开(公告)日：2022-02-01

申请号：US16692742

申请日：2019-11-22

Applicant: EMC IP Holding Company LLC

Inventor： Sandeep Chandrashekhara ,  Michael Ferrari ,  Jeffrey Wilson ,  Mark J. Halstead ,  Art Longden

IPC: G06F11/14 ,  G06F12/1009

Abstract: A no-copy clone of a logical storage unit is created. A define process is initiated for defining a target logical storage unit as the clone before activation of the target logical storage unit. By initiating the define process before activating the logical storage unit, there is a greater likelihood that, when a write operation is received for a data portion on the source logical storage unit or target logical storage unit after activation of the target LSU, the data portion will already be defined and not need to be defined when performing the write operation. When a write operation is received at the source logical storage unit, if the target logical storage unit is not active yet, the data of the write operation may be written to an allocated physical location for the data portion shared between the source and target logical storage units without updating any clone metadata.

公开(公告)号：US20210374017A1

公开(公告)日：2021-12-02

申请号：US16885702

申请日：2020-05-28

Applicant: EMC IP Holding Company LLC

Inventor： Kevin M. Tobin ,  Andrew L. Chanler ,  Michael Ferrari ,  Jeffrey Wilson

IPC: G06F11/14 ,  G06F3/06

Abstract: Snapshots may be managed on a data storage system including logical storage unit including data portions. For a first logical storage unit, a first snapshot pointer structure may be provided including entries, each entry corresponding to a physical storage location at which data is stored for a data portion of the first logical storage unit at a particular point in time. A first virtual snapshot lookup table may be provided for a first portion of the first logical storage unit, the first virtual snapshot lookup table including a plurality of entries, each entry corresponding to a respective data portion of the first logical storage unit and including a reference to a respective entry of the first snapshot pointer structure. The virtual lookup table may correspond to multiple snapshots of the first logical storage unit that have a same value for each data portion of the at least first portion.