Patent ID: 6823442
Filing Date: 2004-11-23
Classification: G06F

Abstract:
A method for writing to a virtual volume mapped to a logical disk, comprising:receiving a request to write a data to the virtual volume at an address; traversing a first table representing the virtual volume to find a first pointer at a first offset based on a first portion of the address, the first pointer leading to one of a plurality of second tables (â€œsaid one second tableâ€ ) also representing the virtual volume; following the first pointer to said one second table; traversing said one second table to find a second pointer at a second offset based on a second portion of the address, the second pointer leading to one of a plurality of third tables (â€œsaid one third tableâ€ ); if said one second table does not exist, determining if a number of available table pages in a first pool is less than a first threshold; if the number of available table pages in the first pool is not less than the first threshold, allocating one table page from the first pool to form said one second table; writing the first pointer at the first offset in the first table.