Method and apparatus for fault tolerant fast writes through buffer dumping

An array controller system for controlling a Write operation for an array of data storage units, including:

• (a) an array controller processor for controlling the Writing of pending Write data to the array of data storage units;
• (b) a first communications adapter, coupled to the array controller processor, for receiving pending Write data from a host over a first communications bus and writing the pending Write data to the array of data storage units over the first communications bus under the control of the array controller processor;
• (c) a first memory device for storing pending Write data;
• (d) a first memory interface, coupled to the first memory device, the array controller processor, the communications adapter, and a second communications bus, for:
• (1) receiving pending Write data from the first communications adapter and storing in the first memory device the received pending Write data;
• (2) reading, under control of the array controller processor, pending Write data from the first memory device and coupling the read pending Write data to the first communications adapter for completing the Write to the array of data storage units;
• (3) controlling communications with an external device, the communications being sent over the second communications bus, such that pending Write data stored within the first memory device can be read and communicated to the external device via the second communications bus upon a failure of the array controller processor.