公开(公告)号：WO2022094895A1

公开(公告)日：2022-05-12

申请号：PCT/CN2020/126866

申请日：2020-11-05

Applicant: ALIBABA GROUP HOLDING LIMITED

Inventor： LU, Qingda ,  PANG, Zhu ,  WU, Jiesheng ,  ZHAO, Xingsheng ,  QIU, Sheng ,  ZHANG, Xiaowei ,  DU, Yu ,  ZHU, Feng ,  CHEN, Shuo ,  XU, Yikang

IPC: G06F3/06

Abstract: Methods and systems implement a virtual copy operation which improves support of preemptive garbage collection policies at a distributed file system. A garbage collection process preemptively performs copying upon data in a log-structured file system. So that thread-blocking write operations are not distributed across nodes of a distributed file system node cluster, and thus avoid degradation of computational performance, a virtual copy operation is provided which, based on master node metadata, locates each chunk node storing blocks to be virtual copied and calls a remap API of a logical address mapper provided by a local file system of the chunk node. The logical address mapper of each chunk node performs remaps of disk addresses from source logical block addresses to destination block addresses, without relocating data from one disk address to another. The results of these remaps may be stored as metadata at the master node, replacing previously mapped metadata.