Method of and system for scheduling transmission of I/O operations

1. A method of scheduling transmission of a plurality of input/output (I/O) operations to be executed by a storage device, the storage device being part of a computer system having:

an operations scheduler executing a scheduling algorithm for scheduling the plurality of I/O operations for transmission to the storage device, the operations scheduler being configured to generate a scheduled sequence having the plurality of I/O operations ordered starting with a first I/O operation to be transmitted and finishing with a last I/O operation to be transmitted;

an I/O operations dispatch controller communicatively coupled to the operations scheduler and the storage device;

the storage device being configured to execute an execution order algorithm to determine an execution order of I/O operations having been transmitted from the operations scheduler for execution;

the method executable by the I/O operations dispatch controller, the method comprising:

applying a slidable N-cell window to select N sequential I/O operations from the scheduled sequence, the slidable N-cell being positioned over the N sequential I/O operations starting with the first I/O operation, each cell of the slidable window including a respective one of the N sequential I/O operations;

transmitting to the storage device the N sequential I/O operations;

receiving an execution confirmation from the storage device that is indicative of a given I/O operation from the N sequential I/O operations having been processed by the storage device;

determining a position of a given cell of the slidable N-cell window associated with the given I/O operation;

responsive to the position of the given cell being the first position amongst positions of cells of the slidable N-cell window:

sliding the slidable N-cell window over the plurality of I/O operations so as to include at least one additional I/O operation in the slidable N-cell window, the at least one additional I/O operation being immediately sequential in the scheduled sequence of the plurality of I/O operations to the N sequential I/O operations; and

transmitting to the storage device, the at least one additional I/O operation for execution.

2. The method of claim 1 , wherein the method further comprises:

responsive to the position of the given cell not being the first position amongst the positions of the cells of the N-cell window:

blocking the slidable N-cell window from sliding over the scheduled sequence of the plurality of I/O operations.

3. The method of claim 1 , wherein the at least one additional I/O operation is present within the scheduled sequence and wherein the transmitting the at least one additional I/O operation to the storage device is executed at the same time as the execution confirmation is received.

4. The method of claim 1 , wherein the at least one additional I/O operation is not present within the scheduled sequence and wherein the transmitting the at least one additional I/O operation to the storage device is executed after the execution confirmation is received as soon as the at least one additional I/O operation is received from the operations scheduler and is added to the scheduled sequence.

5. The method of claim 1 , wherein the receiving the execution confirmation comprises receiving a plurality of confirmations corresponding to a plurality of sequential I/O operations from the N sequential I/O operations having been processed by the storage device, and wherein the sliding of the slidable window is executed over a number of X-cells, the number of X-cells corresponding to a number of executed sequential I/O operations in the plurality of I/O operations starting with the first I/O operation.

6. The method of claim 1 , wherein the I/O operations dispatch controller is implemented as a software module.

7. The method of claim 6 , wherein the software module is located on the storage device.

8. The method of claim 1 , wherein the I/O operations dispatch controller is implemented as a state machine.

9. The method of claim 1 , wherein the scheduling algorithm is FAIR-principle based.

10. The method of claim 1 , wherein the storage device is implemented as a fault tolerant device.

11. The method of claim 1 , wherein the execution order algorithm is uncontrollable by the task scheduler.

12. The method of claim 1 , wherein the method further comprises executing, by the storage device the given I/O operation.

13. The method of claim 1 , wherein the method further comprises transmitting, by the storage device to the I/O operations dispatch controller, information indicative of the given I/O operation having been executed.

14. A system for scheduling transmission of a plurality of input/output (I/O) operations to be executed by a storage device connected to the system, the system having:

an operations scheduler executing a scheduling algorithm for scheduling the plurality of I/O operations for transmission to the storage device, the operations scheduler being configured to generate a scheduled sequence having the plurality of I/O operations ordered starting with a first I/O operation to be transmitted and finishing with a last I/O operation to be transmitted,

an I/O operations dispatch controller communicatively coupled to the operations scheduler and the storage device,

the storage device being configured to execute an execution order algorithm to determine an execution order of I/O operations having been transmitted from the operations scheduler for execution,

the system comprising:

a processor;

a non-transitory computer-readable medium comprising instructions;

the processor, upon executing the instructions, being configured to cause the I/O operations dispatch controller to:

apply a slidable N-cell window to select N sequential I/O operations from the scheduled sequence, the slidable N-cell being positioned over the N sequential I/O operations starting with the first I/O operation, each cell of the slidable window including a respective one of the N sequential I/O operations;

transmit to the storage device the N sequential I/O operations;

receive an execution confirmation from the storage device that is indicative of a given I/O operation from the N sequential I/O operations having been processed by the storage device;

determine a position of a given cell of the slidable N-cell window associated with the given I/O operation;

responsive to the position of the given cell being the first position amongst positions of cells of the slidable N-cell window:

slide the slidable N-cell window over the plurality of I/O operations so as to include at least one additional I/O operation in the slidable N-cell window, the at least one additional I/O operation being immediately sequential in the scheduled sequence of the plurality of I/O operations to the N sequential I/O operations; and

transmit to the storage device, the at least one additional I/O operation for execution.

15. The system of claim 14 , wherein the processor is further configured to cause the I/O operations dispatch controller to:

responsive to the position of the given cell not being the first position amongst the positions of the cells of the N-cell window:

block the slidable N-cell window from sliding over the scheduled sequence of the plurality of I/O operations.

16. The system of claim 14 , wherein the at least one additional I/O operation is present within the scheduled sequence and wherein the transmitting the at least one additional I/O operation to the storage device is executed at the same time as the execution confirmation is received.

17. The system of claim 14 , wherein the at least one additional I/O operation is not present within the scheduled sequence and wherein the transmitting the at least one additional I/O operation to the storage device is executed after the execution confirmation is received as soon as the at least one additional I/O operation is received from the operations scheduler and is added to the scheduled sequence.

18. The system of claim 14 , wherein the receiving the execution confirmation comprises receiving a plurality of confirmations corresponding to a plurality of sequential I/O operations from the N sequential I/O operations having been processed by the storage device, and wherein the sliding of the slidable window is executed over a number of X-cells, the number of X-cells corresponding to a number of executed sequential I/O operations in the plurality of I/O operations starting with the first I/O operation.

19. The system of claim 14 , wherein the I/O operations dispatch controller is implemented as a software module and wherein the instructions are part of the software module.

20. The system of claim 19 , wherein the software module is located on the storage device.

21. The system of claim 14 , wherein the I/O operations dispatch controller is implemented as a state machine and wherein the instructions are part of the state machine.

22. The system of claim 14 , wherein the scheduling algorithm is FAIR-principle based.

23. The system of claim 14 , wherein the storage device is implemented as a fault tolerant device.

24. The system of claim 14 , wherein the execution order algorithm is uncontrollable by the task scheduler.

25. The system of claim 14 , wherein the processor is further configured to cause the I/O operations to cause execution of the given I/O operation by the storage device.

26. The system of claim 14 , wherein the processor is further configured to cause the I/O operations to cause transmission, by the storage device, information indicative of the given I/O operation having been executed.