Fei Zhou, 51310 Thackeray Ln, Northfield, IL 60093

7403945, Jul 22, 2008

Nov 1, 2004

10/904263

Mei-Lin Linda Lin - San Jose CA, US
Fei Zhou - Glenview IL, US
Joe Francis - Fremont CA, US
Srikanth Sampath - Fremont CA, US
Satya N. Ramachandran - Fremont CA, US
Gangavara Prasad Varakur - Pleasanton CA, US

Sybase, Inc. - Dublin CA

G06F 17/30

707 8

A distributed database system providing data and space management methodology is described. In one embodiment, for example, a method is described for detection of deadlocks in a distributed database system comprising a plurality of servers sharing access to data, the method comprises steps of: in response to a task at a first server waiting to obtain a lock regulating access to data, sending a search request including lock information to a second server holding the lock; at the second server, examining dependencies of the task holding the lock based on the lock information received with the search request and local lock information; if the task holding the lock is waiting to obtain a lock held by an additional server, forwarding the search request and local lock information to the additional server; repeating the examining and forwarding steps until all dependencies are examined; and responding to the search request indicating whether a deadlock was detected and providing lock information found.

7447710, Nov 4, 2008

Aug 9, 2004

10/710868

Srikanth Sampath - Fremont CA, US
Fei Zhou - Glenview IL, US
Girish Vaitheeswaran - Fremont CA, US
Prasanta Ghosh - San Ramon CA, US

Sybase, Inc. - Dublin CA

G06F 12/00
G06F 17/30

707202, 707200, 707204, 718100, 718104

A database system providing self-tuned parallel database recovery is described. In one embodiment, for example, in a database system, a method is described for performing recovery operations using an optimal number of recovery threads, the method comprises steps of: (a) spawning an initial recovery thread to perform recovery operations; (b) measuring I/O (input/output) performance with the initial recovery thread; (c) spawning a subsequent recovery thread to perform recovery operations; (d) measuring I/O performance with the subsequent recovery thread; and (e) as long as I/O performance does not degrade beyond a preselected percentage, repeating steps (c) and (d) for spawning a desired number of additional recovery threads. In another embodiment, the database system auto-tunes the cache during performance of database recovery operations to optimize the performance of recovery operations.

7783610, Aug 24, 2010

Feb 22, 2008

12/035930

Mei-Lin Linda Lin - San Jose CA, US
Fei Zhou - Glenview IL, US
Joe Francis - Fremont CA, US
Srikanth Sampath - Fremont CA, US
Satya N. Ramachandran - Fremont CA, US
Gangavara Prasad Varakur - Pleasanton CA, US

Sybase, Inc. - Dublin CA

G06F 17/30

707689, 707695, 709203, 709219

A distributed database system providing data and space management methodology. In a distributed system consisting a plurality of servers sharing access to data pages, a method for setting a timestamp indicating when modifications to data pages are made in a non-regressing fashion includes steps of: maintaining a local sequence at each server and an allocation page timestamp on an allocation page; upon allocation of a data page, applying a timestamp to the data page which is greater than the allocation page timestamp; upon modification of a given data page at a particular server, setting the timestamp on the given data page to the greater of the local sequence at the particular server and an existing timestamp already on the given data page; and when data pages are deallocated, adjusting the allocation page timestamp to a value greater than the timestamp value on any deallocated data page.

7899794, Mar 1, 2011

Mar 20, 2008

12/052417

Vadiraja Bhatt - Bangalore, IN
Nitin Verma - Indore, IN
Fei Zhou - Glenview IL, US

Sybase, Inc. - Dublin CA

G06F 17/00

707682, 707672, 707674, 711161, 714 2, 714748

A system, method, and computer program product for improving physical lock acquisition for database transaction logs are described herein. In an embodiment, the method operates by receiving a request for a transaction log page and determining whether a requested log page is newly-allocated or already exists. A determination is made regarding whether the last log page is being modified. A physical lock is taken on the requested log page when it has been determined that the requested log page is not newly-allocated and that the last log page is not being modified. Operations on the last log page are synchronized without a physical lock when it is determined that the requested log page is newly-allocated or that the last log page is being modified.

8266111, Sep 11, 2012

Mar 26, 2008

12/056201

Mei-Lin Linda Lin - San Jose CA, US
Fei Zhou - Glenview IL, US
Joe Francis - Fremont CA, US
Srikanth Sampath - Fremont CA, US
Satya N. Ramachandran - Fremont CA, US
Gangavara Prasad Varakur - Livermore CA, US

Sybase, Inc. - Dublin CA

G06F 7/00

707674

A distributed database system providing data and space management methodology. In a distributed database system having an allocation page for tracking allocation and deallocation of data pages including a deallocation bit for tracking data page deallocation, a method for determining when to clear the deallocation bit during recovery comprises: during runtime operation, generating log records recording allocation and deallocation of data pages, setting the deallocation bit during deallocation of a data page by a transaction, and clearing the deallocation bit after the transaction has committed; during recovery following a failure, identifying a particular log record corresponding to the deallocation bit set during deallocation of a given data page; determining whether the deallocation of the given data page recorded in the particular log record committed prior to the failure; and if the deallocation of the given data page committed prior to the failure, clearing the deallocation bit.

2008017, Jul 17, 2008

Mar 25, 2008

12/055194

Mei-Lin Linda Lin - San Jose CA, US
Fei Zhou - Glenview IL, US
Joe Francis - Fremont CA, US
Srikanth Sampath - Fremont CA, US
Satya N. Ramachandran - Fremont CA, US
Gangavara Prasad Varakur - Livermore CA, US

SYBASE, INC. - Dublin CA

G06F 17/00
G06F 9/46
G06F 9/44

707205, 718105, 719318, 707E17005

A distributed database system providing data and space management methodology. In one embodiment a system for allocating resources amongst a plurality of database servers sharing resources comprises: an input module for receiving user input for allocating resources shared amongst a plurality of database servers and establishing thresholds for utilization of resources at each database server; a monitoring module at each database server for monitoring local resource utilization at each database server and sending a request for balancing resources to a second database server when local resource utilization reaches an established threshold at a first database server; and a load balancing module for receiving the request for balancing resources and determining whether to adjust resources allocated to the first database server and the second database server in response to the request.

2008029, Nov 27, 2008

Feb 26, 2008

12/037791

Mei-Lin Linda Lin - San Jose CA, US
Fei Zhou - Glenview IL, US
Joe Francis - Fremont CA, US
Srikanth Sampath - Fremont CA, US
Satya N. Ramachandran - Fremont CA, US
Gangavara Prasad Varakur - Pleasanton CA, US

Sybase, Inc. - Dublin CA

G06F 17/30

707 10, 707E1701

A distributed database system providing data and space management methodology. In one embodiment, for example, a method for transferring a data structure in cache at a first database server to a second database server in a distributed database system comprises steps of: determining a first database server having a data structure in cache in response to a request for the data structure from a second database server, the request including a request for a lock on the data structure; providing the request for the data structure to the first database server; in response, sending the data structure from the first database server to the second database server; and receiving and using the data structure at the second database server without waiting for the lock request to be explicitly granted.

2021035, Nov 18, 2021

May 18, 2020

16/877328

- Addison TX, US
Rahul SHARANGPANI - Fremont CA, US
Raghuveer S. MAKALA - Campbell CA, US
Fei ZHOU - San Jose CA, US
Yanli ZHANG - San Jose CA, US

H01L 27/11582
H01L 27/11565
H01L 27/1157
H01L 27/11543
H01L 27/11524
H01L 27/11556
H01L 27/11519

A method of forming a three-dimensional memory device includes forming an alternating stack of insulating layers and sacrificial material layers over a substrate, forming a memory opening through the alternating stack, forming lateral recesses at levels of the sacrificial material layers around the memory opening, forming a vertical stack of discrete clam-shaped semiconductor liners in the lateral recesses, replacing the vertical stack of discrete clam-shaped semiconductor liners with a vertical stack of inner clam-shaped metallic liners, forming a vertical stack of discrete charge storage elements on the vertical sack of inner clam-shaped metallic liners, forming a tunneling dielectric layer and a vertical semiconductor channel over the vertical stack of discrete charge storage elements and the vertical stack of inner clam-shaped metallic liners, and replacing each of the sacrificial material layers with an electrically conductive layer.