Prefetching operations in storage devices
Provided is a method of adjusting prefetching operations, the method including setting a prefetching distance, accessing a prefetching-trigger key, determining a target key is outside of the prefetching distance from the prefetching-trigger key, increasing the prefetching distance, and successfully fetching a subsequent target key of a subsequent prefetching-trigger key from a prefetching read-ahead buffer.
1. A method of adjusting prefetching operations, the method comprising:
setting a prefetching distance;
accessing a prefetching-trigger key;
determining a target key is outside of the prefetching distance from the prefetching-trigger key;
increasing the prefetching distance; and
successfully fetching a subsequent target key of a subsequent prefetching-trigger key from a prefetching read-ahead buffer.
2. The method of claim 1 , wherein increasing the prefetching distance comprises increasing the prefetching distance exponentially.
3. The method of claim 1 , further comprising:
determining that the prefetching read-ahead buffer has overflown; and
inserting an entry corresponding to an additional subsequent prefetching-trigger key into a cache of a key-value database.
4. The method of claim 3 , further comprising:
determining the subsequent prefetching-trigger key is present in the simulation cache; and
reinitiating prefetching operations.
5. The method of claim 1 , further comprising:
determining an additional subsequent prefetching-trigger key is missing from the prefetching read-ahead buffer; and
skipping a prefetching operation for an additional subsequent target key of the additional subsequent prefetching-trigger key.
6. The method of claim 5 , further comprising decreasing the prefetching distance.
7. The method of claim 6 , wherein decreasing the prefetching distance comprises decreasing the prefetching distance by one key.
8. A system for managing prefetching operations for transferring data from a storage device to a prefetching read-ahead buffer, the system being configured to:
set a prefetching distance;
access a prefetching-trigger key;
determine a target key is outside of the prefetching distance from the prefetching-trigger key;
increase the prefetching distance; and
successfully fetch a subsequent target key of a subsequent prefetching-trigger key from the prefetching read-ahead buffer.
9. The system of claim 8 , wherein the system is configured to increase the prefetching distance by increasing the prefetching distance exponentially.
10. The system of claim 8 , wherein the system is further configured to:
determine that the prefetching read-ahead buffer has overflown; and
insert an entry corresponding to an additional subsequent prefetching-trigger key into a cache of a key-value database of the system.
11. The system of claim 10 , wherein the system is further configured to:
determine the subsequent prefetching-trigger key is present in the simulation cache; and
reinitiate prefetching operations.
12. The system of claim 8 , wherein the system is further configured to:
determine an additional subsequent prefetching-trigger key is missing from the prefetching read-ahead buffer; and
skip a prefetching operation for an additional subsequent target key of the additional subsequent prefetching-trigger key.
13. The system of claim 12 , wherein the system is further configured to decrease the prefetching distance.
14. The system of claim 13 , wherein the system is configured to decrease the prefetching distance by decreasing the prefetching distance by one key.
15. A non-transitory computer readable medium implemented on a system for managing prefetching operations for transferring data from a storage device to a prefetching read-ahead buffer, the non-transitory computer readable medium having computer code that, when executed on a processor, implements a method of adjusting prefetching operations, the method comprising:
setting a prefetching distance;
accessing a prefetching-trigger key;
determining a target key is outside of the prefetching distance from the prefetching-trigger key;
increasing the prefetching distance; and
successfully fetching a subsequent target key of a subsequent prefetching-trigger key from a prefetching read-ahead buffer.
16. The non-transitory computer readable medium of claim 15 , wherein the computer code, when executed on a processor, is configured to increase the prefetching distance by increasing the prefetching distance exponentially.
17. The non-transitory computer readable medium of claim 15 , wherein the computer code, when executed on a processor, further implements the method of adjusting prefetching operations by:
determining that the prefetching read-ahead buffer has overflown; and
inserting an entry corresponding to an additional subsequent prefetching-trigger key into a cache of a key-value database.
18. The non-transitory computer readable medium of claim 17 , wherein the computer code, when executed on a processor, further implements the method of adjusting prefetching operations by:
determining the subsequent prefetching-trigger key is present in the simulation cache; and
reinitiating prefetching operations.
19. The non-transitory computer readable medium of claim 15 , wherein the computer code, when executed on a processor, further implements the method of adjusting prefetching operations by:
determining an additional subsequent prefetching-trigger key is missing from the prefetching read-ahead buffer; and
skipping a prefetching operation for an additional subsequent target key of the additional subsequent prefetching-trigger key.
20. The non-transitory computer readable medium of claim 19 , wherein the computer code, when executed on a processor, further implements the method of adjusting prefetching operations by decreasing the prefetching distance.