Host-controlled garbage collection
In an array of solid-state drives (SSDs), SSDs in the array are each configured to initiate generation of additional erased memory blocks when an initiation command is received from a host or when the number of erased memory blocks in the SSD falls below a minimum threshold of erased memory blocks for the SSD. The minimum threshold value may be adjusted by the host.
1. A host computing device connectable to a data storage device and including a data storage storing a control algorithm to cause the host computing device to carry out a method of writing data to the data storage device, which includes a pool of non-volatile solid-state devices, the method comprising:
sending an inquiry to a first non-volatile solid-state device in the pool of non-volatile solid-state devices for a number of erased memory blocks in the first non-volatile solid-state device;
after receiving from the first non-volatile solid-state device the number of erased memory blocks in the first non-volatile solid-state device, writing to the first non-volatile solid-state device a quantity of data equal to or less than the number of erased memory blocks received from the first non-volatile solid-state device;
in response to an acknowledgement that writing the quantity of data to the first non-volatile solid-state device has completed, sending a command to the first non-volatile solid-state device to begin generating erased memory blocks in the first non-volatile solid-state device; and
while writing the quantity of data to the first non-volatile solid-state device, sending an inquiry to a second non-volatile solid-state device in the pool of non-volatile solid-state devices for a number of erased memory blocks in the second non-volatile solid-state device.
2. The host computing device of claim 1 , wherein the method further comprises:
upon receiving from the first non-volatile solid-state device a notification that a number of erased memory blocks currently present in the first non-volatile solid-state storage device is less than a notification threshold, sending a command to the first non-volatile solid-state device to begin generating erased memory blocks in the first non-volatile solid-state device.
3. The host computing device of claim 2 , wherein the notification threshold corresponds to a number of erased memory blocks in the first non-volatile solid-state storage device that is greater than a minimum threshold value of erased memory blocks at which the controller begins generating erased blocks in the first non-volatile solid-state storage device.
4. The host computing device of claim 3 , wherein the method further comprises, prior to sending the inquiry to the first non-volatile solid-state device, sending the minimum threshold value to the first non-volatile solid-state device.
5. The host computing device of claim 2 , wherein the method further comprises, while writing the quantity of data to the first non-volatile solid-state device, turning into a state for receiving from the second non-volatile solid-state device the number of erased memory blocks in the second non-volatile solid-state device.
6. The host computing device of claim 5 , wherein the method further comprises, in response to the acknowledgement that writing the quantity of data to the first non-volatile solid-state device has completed, writing to the second non-volatile solid-state device a quantity of data equal to or less than the number of erased memory blocks received from the second non-volatile solid-state device.
7. The host computing device of claim 1 , wherein the method further comprises, prior to sending the inquiry to the first non-volatile solid-state device, enabling the first non-volatile solid-state device to receive and respond to the inquiry.
8. The host computing device of claim 7 , wherein enabling the first non-volatile solid-state device to receive and respond to the inquiry comprises sending a system interface command to the first non-volatile solid-state device, the system interface command including a field assigned to enable the first non-volatile solid-state device to receive and respond to the inquiry.
9. The host computing device of claim 8 , wherein the system interface command comprises one of a Serial Advanced Technology Attachment (SATA) command, a Serial Attached Small Computer System Interface (SAS) command, or a Non-Volatile Memory Express (NVMe) command.