Patent ID: 8370591
Filing Date: 2013-02-05
Classification: G06F

Abstract:
1. A method for automatic snapshot, comprising: resetting an increment accumulation variable which indicates a total amount of data written to a source Logical Unit Number (LUN), to zero; after resetting the increment accumulation variable to zero, determining whether there is an operation of writing to the source LUN; obtaining an amount of data which is written to the source LUN in the operation if the operation of writing to the source LUN is determined, wherein the amount of the data is a value indicating the number of bytes of the data which is written to the source LUN in the operation; accumulating the number of bytes of the data which is written to the source LUN in the operation for the increment accumulation variable; obtaining the total amount of data written to the source LUN; determining whether the total amount of data written to the source LUN exceeds a preset upper limit value; taking a snapshot upon determining that the total amount of data written to the source LUN exceeds the preset upper limit value, and reset the increment accumulation variable to zero again; and determining whether there is another operation of writing to the source LUN on determining that the total amount of data written to the source LUN does not exceed the preset upper limit value.