公开(公告)号：US11353917B1

公开(公告)日：2022-06-07

申请号：US16992673

申请日：2020-08-13

Applicant: Google LLC

Inventor： Peter Hochschild ,  Alexander Lloyd ,  Wilson Cheng-Yi Hsieh ,  Robert Edman Felderman ,  Michael James Boyer Epstein

IPC: G06F1/12 ,  G01S19/01 ,  H04L7/00 ,  H04J3/06 ,  H04L67/10 ,  H04L43/106 ,  G06F11/16

Abstract: The present technology proposes techniques for generating globally coherent timestamps. This technology may allow distributed systems to causally order transactions without incurring various types of communication delays inherent in explicit synchronization. By globally deploying a number of time masters that are based on various types of time references, the time masters may serve as primary time references. Through an interactive interface, the techniques may track, calculate and record data relative to each time master thus providing the distributed systems with causal timestamps.

公开(公告)号：US20210185126A1

公开(公告)日：2021-06-17

申请号：US17189646

申请日：2021-03-02

Applicant: Google LLC

Inventor： Wilson Cheng-Yi Hsieh ,  Peter Hochschild

IPC: H04L29/08 ,  G06F16/23 ,  G06F16/176 ,  H04L29/06

Abstract: Throughput is preserved in a distributed system while maintaining concurrency by pushing a commit wait period to client commit paths and to future readers. As opposed to servers performing commit waits, the servers assign timestamps, which are used to ensure that causality is preserved. When a server executes a transaction that writes data to a distributed database, the server acquires a user-level lock, and assigns the transaction a timestamp equal to a current time plus an interval corresponding to bounds of uncertainty of clocks in the distributed system. After assigning the timestamp, the server releases the user-level lock. Any client devices, before performing a read of the written data, must wait until the assigned timestamp is in the past.