4.2.09. Timestamping

  • Transaction T issues read_item(X)
    • TO algorithm compares TS(T) with Write_TS(X)
    • Ensures transaction order execution not violated
  • If successful,Write_TS(X) <= TS(T)
    • Read_TS(X) = MAXTS(T), current Read_TS(X)
  • If fail,Write_TS(X) > TS(T)
    • T aborted, rolled-back and resubmitted with new TS
    • Cascading rollback