公开(公告)号：US20210373893A1

公开(公告)日：2021-12-02

申请号：US16883241

申请日：2020-05-26

Applicant: SAP SE

Inventor： Dirk Thomsen ,  Thorsten Glebe ,  Tobias Scheuer ,  Werner Thesing ,  Johannes Gloeckle

IPC: G06F9/30 ,  G06F16/28 ,  G06F9/38 ,  G06F9/54

Abstract: Aspects of the current subject matter are directed to an approach in which a parallel load operation of file ID mapping containers is accomplished at start and/or restart of a database system. Parallel load operation of file ID mapping and/or large binary object (LOB) file ID mapping is done among a plurality of scanning engines into a plurality of data buffers that are associated with each of the plurality of scanning engines. Each scanning engine operates on a certain path of a page chain of a page structure including the mapping, causing the page chain to be split among scanning engines to process maps. Contents of the data buffers are pushed to mapping engines via a queue. The mapping engines load the file ID mapping and the LOB file ID mapping into maps for in-system access.

公开(公告)号：US10983965B2

公开(公告)日：2021-04-20

申请号：US16544739

申请日：2019-08-19

Applicant: SAP SE

Inventor： Chul Won Lee ,  Daniel Booss ,  Jaeyoung Choi ,  Werner Thesing

IPC: G06F12/00 ,  G06F3/06 ,  G06F16/21

Abstract: Receiving a statement including requests for database operations in a secondary database system storing data replicated from a primary database system by replaying transaction output generated by the primary database system; responsive to receiving the statement, requesting an allocation of memory from the secondary database system to support the requested database operations; generating an aggregated statement memory consumption value based on the amount of memory consumed by all statements executing in the secondary database system that are not associated with replaying the transaction logs; determining that the requested allocation of memory in addition to the aggregated statement memory consumption value exceeds a total statement execution memory limit indicating a total amount of memory that may be allocated to all database operations associated with statement execution in a secondary database system, and denying the requested allocation of memory. Related apparatus, systems, techniques and articles are also described.

公开(公告)号：US20180239676A1

公开(公告)日：2018-08-23

申请号：US15436535

申请日：2017-02-17

Applicant: SAP SE

Inventor： Thorsten Glebe ,  Werner Thesing ,  Christoph Roterring

IPC: G06F11/14 ,  G06F12/02 ,  G06F17/30

CPC classification number: G06F11/1469 ,  G06F11/1471 ,  G06F11/2038 ,  G06F11/2094 ,  G06F11/2097 ,  G06F12/0253 ,  G06F2212/1041 ,  G06F2212/1044 ,  G06F2212/702

Abstract: Recovery of a database system by taking the database system offline is initiated. Thereafter, recovery operations specified by a redo log of the database system are replayed. A cleanup log is generated that identifies cleanup operations occurring during the replay of the recovery operations for garbage collection. Concurrent with the startup of the database, garbage collection of the cleanup operations as specified in the database savepoint is initiated. In addition, concurrent with the replay of the recovery operations, garbage collection of the cleanup operations specified by the cleanup log is initiated. The database system is later brought online after all of the recovery operations are replayed.

公开(公告)号：US11379323B2

公开(公告)日：2022-07-05

申请号：US16704727

申请日：2019-12-05

Applicant: SAP SE

Inventor： Kyu Hwan Kim ,  Deok Hoe Kim ,  Beomsoo Kim ,  Juchang Lee ,  Werner Thesing ,  Christoph Roterring

IPC: G06F11/00 ,  G06F11/14 ,  G06F16/23 ,  G06F16/27 ,  G06F11/20 ,  G06F11/30 ,  G06F11/07

Abstract: A computer implemented method is provided for determining a delay between a first database and an associated replicated database by replicating transactions of the first database in the replicated database, determining a delay between the two databases based on a commit timestamp from the first database and a timestamp associated with the commit transaction becoming visible in the replicated database. Then, after a predefined period of time has elapsed since replicating the commit transaction, determining a second delay based on a timestamp associated with a heartbeat log and a replicated database system time. And, selectively determining to execute or deny a statement received by the replicated database based on the second delay. Related apparatus, systems, techniques and articles are also described.

公开(公告)号：US10824673B2

公开(公告)日：2020-11-03

申请号：US15695621

申请日：2017-09-05

Applicant: SAP SE

Inventor： Oliver Rebholz ,  Ivan Schreter ,  Abdelkader Sellami ,  Daniel Booss ,  Gunter Radestock ,  Peter Bumbulis ,  Alexander Boehm ,  Frank Renkes ,  Werner Thesing ,  Thomas Willhalm

IPC: G06F16/901 ,  G06F3/06

Abstract: A system includes a non-volatile random access memory storing a column store main fragment of a column of a database table, and a processing unit to read the column store main fragment from the non-volatile random access memory. A volatile random access memory storing a column store delta fragment of the column of the database table may also be included, in which the processing unit is to write to the column store delta fragment. According to some systems, the stored column store main fragment is byte-addressable, and is copied from the volatile random access memory to the non-volatile random access memory without using a filesystem cache.

公开(公告)号：US20180246928A1

公开(公告)日：2018-08-30

申请号：US15442906

申请日：2017-02-27

Applicant: SAP SE

Inventor： Kyu Hwan Kim ,  Deok Hoe Kim ,  Beomsoo Kim ,  Juchang Lee ,  Werner Thesing ,  Christoph Roterring

IPC: G06F17/30 ,  G06F11/14

Abstract: A computer implemented method is provided for determining a delay between a first database and an associated replicated database by replicating transactions of the first database in the replicated database, determining a delay between the two databases based on a commit timestamp from the first database and a timestamp associated with the commit transaction becoming visible in the replicated database. Then, after a predefined period of time has elapsed since replicating the commit transaction, determining a second delay based on a timestamp associated with a heartbeat log and a replicated database system time. And, selectively determining to execute or deny a statement received by the replicated database based on the second delay. Related apparatus, systems, techniques and articles are also described.

公开(公告)号：US20180150496A1

公开(公告)日：2018-05-31

申请号：US15361760

申请日：2016-11-28

Applicant: SAP SE

Inventor： Kyu Hwan Kim ,  Juchang Lee ,  Beomsoo Kim ,  Chang Gyoo Park ,  Reiner Singer ,  Christoph Rottering ,  Werner Thesing ,  Michael Muehle

IPC: G06F17/30

CPC classification number: G06F16/2322 ,  G06F16/2365 ,  G06F16/2379 ,  G06F16/2386 ,  G06F16/245 ,  G06F16/27 ,  G06F16/273

Abstract: A computer implemented method is provided comprising receiving a group of transaction logs from a first database, allocating transaction logs from the group of transaction logs to a first queue and to a second queue, generating an end-of-group transaction log indicative of an end of the group of transaction logs, allocating the end-of-group log to the first queue and the second queue; replaying transaction logs from the first queue including the end-of-group transaction log allocated to the first queue, replaying transaction logs from the second queue including the end-of-group transaction log allocated to the second queue; and changing visibility of one or more transactions in response to replaying the end-of-group transaction log allocated to the first queue and the end-of-group transaction log allocated to the second queue. Related apparatus, systems, techniques and articles are also described.

公开(公告)号：US20250045297A1

公开(公告)日：2025-02-06

申请号：US18228446

申请日：2023-07-31

Applicant: SAP SE

Inventor： Markus Behrens ,  Reiner Singer ,  Werner Thesing ,  Yue Zhu ,  Omran Saleh

IPC: G06F16/27

Abstract: Various examples are directed to systems and methods for operating a primary database management system and a secondary database management system. The secondary database management system may receive a takeover request indicating that the secondary database management system is to assume a role of the primary database system. The secondary database management system may determine that a last valid commit of a first host of the secondary database system is an oldest last valid commit. The secondary database management system may revert to a first state of the primary database management system corresponding to the last valid commit of the first host. The secondary database management system may be configured to assume the role of the primary database management system.

公开(公告)号：US20250045178A1

公开(公告)日：2025-02-06

申请号：US18228395

申请日：2023-07-31

Applicant: SAP SE

Inventor： Markus Behrens ,  Reiner Singer ,  Werner Thesing ,  Yue Zhu ,  Mitja Kleider ,  Omran Saleh ,  Timo Sulg ,  Marcel Birn ,  Christoph Roterring

IPC: G06F11/20 ,  G06F11/16

Abstract: A scale-out computing cluster may include a large number of computing servers and storage devices. In order to provide high reliability, the computing cluster must be able to handle failures of individual devices. Reliability of the computing cluster may be improved by providing a standby server for each active server in the computing cluster. If any active server fails, the corresponding standby server is activated. The failed server may be brought back online or replaced, at which time the restored server becomes the standby server for the now-active original standby server. During the restoration period, if any other active server fails, the standby server for that active server is immediately activated. As a result, the recovery ability of the computing cluster is only challenged if both servers of an active/standby pair fail during the restoration period, substantially improving reliability.

公开(公告)号：US11301341B2

公开(公告)日：2022-04-12

申请号：US16834317

申请日：2020-03-30

Applicant: SAP SE

Inventor： Christoph Roterring ,  Reiner Singer ,  Werner Thesing

IPC: G06F11/20 ,  G06F3/06

Abstract: A method, a system, and a computer program product for executing a takeover process. A takeover process of a primary computing system by a secondary computing system is triggered. The secondary computing system stores transaction data replicated from the primary computing system. Writing of a redo log of transaction data of one or more transactions into storage by the primary computing system is suspended. The redo log is written by the primary computing system prior to the suspending is transmitted to the secondary computing system. The takeover process of the primary computing system by the secondary computing system is executed upon receiving and persisting the redo log at the secondary computing system.